Can't build Stripe's OpenAPI spec with "not yet implemented". panic from proc macro from `typify-impl`

The OpenAPI spec is here.

The failure is at "typify-288d5a84bbbe6a46/25e11d8/typify-impl/src/util.rs:246:25:"

When building with the macro, the error comes from a proc macro panic which offers very little context:

    Checking redacted v0.1.0 (redacted)
error: proc macro panicked
  --> redacted/src/main.rs:40:1
   |
40 | generate_api!("../../../stripe-openapi/openapi/spec3.json");
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: message: not yet implemented

error: could not compile redacted` (bin "redacted") due to 1 previous error

I got more info running it from a build.rs:

 RUST_BACKTRACE=1 cargo c
warning: unused variable: `src`
 --> redacted/build.rs:6:9
  |
6 |     let src = "../../../stripe-openapi/openapi/fixtures3.json";
  |         ^^^ help: if this is intentional, prefix it with an underscore: `_src`
  |
  = note: `#[warn(unused_variables)]` on by default

warning: `redacted` (build script) generated 1 warning
   Compiling redacted v0.1.0 (redacted
error: failed to run custom build command for `redacted v0.1.0 (redacted)`
note: To improve backtraces for build dependencies, set the CARGO_PROFILE_DEV_BUILD_OVERRIDE_DEBUG=true environment variable to enable debug information generation.

Caused by:
  process didn't exit successfully: `redacted/build-script-build` (exit status: 101)
  --- stdout
  cargo:rerun-if-changed=../migrations
  cargo:rerun-if-changed=../../../stripe-openapi/openapi/spec3.json

  --- stderr
  thread 'main' panicked at /Users/nbajskansbbbelopni/.cargo/git/checkouts/typify-288d5a84bbbe6a46/25e11d8/typify-impl/src/util.rs:246:25:
  not yet implemented
  stack backtrace:
     0: rust_begin_unwind
               at /rustc/aedd173a2c086e558c2b66d3743b344f977621a7/library/std/src/panicking.rs:647:5
     1: core::panicking::panic_fmt
               at /rustc/aedd173a2c086e558c2b66d3743b344f977621a7/library/core/src/panicking.rs:72:14
     2: core::panicking::panic
               at /rustc/aedd173a2c086e558c2b66d3743b344f977621a7/library/core/src/panicking.rs:144:5
     3: typify_impl::util::schemas_mutually_exclusive
     4: typify_impl::util::all_mutually_exclusive::{{closure}}
     5: core::iter::traits::iterator::Iterator::all::check::{{closure}}
     6: core::ops::function::impls::<impl core::ops::function::FnMut<A> for &mut F>::call_mut
     7: core::iter::adapters::map::map_try_fold::{{closure}}
     8: core::iter::traits::iterator::Iterator::try_fold
     9: <core::iter::adapters::map::Map<I,F> as core::iter::traits::iterator::Iterator>::try_fold
    10: <core::iter::adapters::flatten::FlattenCompat<I,U> as core::iter::traits::iterator::Iterator>::try_fold::flatten::{{closure}}
    11: core::iter::adapters::flatten::FlattenCompat<I,U>::iter_try_fold::flatten::{{closure}}
    12: core::iter::adapters::map::map_try_fold::{{closure}}
    13: core::iter::traits::iterator::Iterator::try_fold
    14: <core::iter::adapters::map::Map<I,F> as core::iter::traits::iterator::Iterator>::try_fold
    15: <core::iter::adapters::fuse::Fuse<I> as core::iter::adapters::fuse::FuseImpl<I>>::try_fold
    16: core::iter::adapters::flatten::FlattenCompat<I,U>::iter_try_fold
    17: <core::iter::adapters::flatten::FlatMap<I,U,F> as core::iter::traits::iterator::Iterator>::try_fold
    18: core::iter::traits::iterator::Iterator::all
    19: typify_impl::util::all_mutually_exclusive
    20: typify_impl::convert::<impl typify_impl::TypeSpace>::convert_any_of
    21: typify_impl::convert::<impl typify_impl::TypeSpace>::convert_schema_object
    22: typify_impl::convert::<impl typify_impl::TypeSpace>::convert_schema
    23: typify_impl::TypeSpace::id_for_schema
    24: typify_impl::structs::<impl typify_impl::TypeSpace>::struct_property
    25: typify_impl::structs::<impl typify_impl::TypeSpace>::struct_members::{{closure}}
    26: core::iter::adapters::filter_map::filter_map_try_fold::{{closure}}
    27: core::ops::function::impls::<impl core::ops::function::FnMut<A> for &mut F>::call_mut
    28: core::iter::traits::iterator::Iterator::try_fold
    29: <core::iter::adapters::chain::Chain<A,B> as core::iter::traits::iterator::Iterator>::try_fold
    30: <core::iter::adapters::filter_map::FilterMap<I,F> as core::iter::traits::iterator::Iterator>::try_fold
    31: <core::iter::adapters::GenericShunt<I,R> as core::iter::traits::iterator::Iterator>::try_fold
    32: <core::iter::adapters::GenericShunt<I,R> as core::iter::traits::iterator::Iterator>::next
    33: alloc::vec::Vec<T,A>::extend_desugared
    34: <alloc::vec::Vec<T,A> as alloc::vec::spec_extend::SpecExtend<T,I>>::spec_extend
    35: <alloc::vec::Vec<T> as alloc::vec::spec_from_iter_nested::SpecFromIterNested<T,I>>::from_iter
    36: <alloc::vec::Vec<T> as alloc::vec::spec_from_iter::SpecFromIter<T,I>>::from_iter
    37: <alloc::vec::Vec<T> as core::iter::traits::collect::FromIterator<T>>::from_iter
    38: <core::result::Result<V,E> as core::iter::traits::collect::FromIterator<core::result::Result<A,E>>>::from_iter::{{closure}}
    39: core::iter::adapters::try_process
    40: <core::result::Result<V,E> as core::iter::traits::collect::FromIterator<core::result::Result<A,E>>>::from_iter
    41: core::iter::traits::iterator::Iterator::collect
    42: typify_impl::structs::<impl typify_impl::TypeSpace>::struct_members
    43: typify_impl::convert::<impl typify_impl::TypeSpace>::convert_object
    44: typify_impl::convert::<impl typify_impl::TypeSpace>::convert_schema_object
    45: typify_impl::convert::<impl typify_impl::TypeSpace>::convert_schema
    46: typify_impl::TypeSpace::convert_ref_type
    47: typify_impl::TypeSpace::add_ref_types_impl
    48: typify_impl::TypeSpace::add_ref_types
    49: progenitor_impl::Generator::generate_tokens
    50: build_script_build::main
    51: core::ops::function::FnOnce::call_once
  note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

Reproduce the failure using Stripe's openapi/spec3.json and inspect typify-impl/src/util.rs:246, especially schemas_mutually_exclusive and its callers in the backtrace. Trace which schema combination triggers the panic, then use the build-script reproduction to verify the behavior after the issue is addressed.