Issues connecting when "Further authentication" is prompted

Referencing darkoperator/posh-ssh#443

The author of said project has responded saying SSH.NET does not support further authentication prompts.
The server in question requires both a username+key, followed by a prompt for an OTP code.

When using said project:
Using PoSH-SSH 3.0.0 does not work for me when the server is setup to accept keys, with a prompt during auth for OTP.
Example: auth using "user" with key (empty pass), in PuTTy its seen as:

login as: user
Authenticating with public key "rsa-key...." from agent
Further authentication required
Keyboard-interactive authentication prompts from server:
| OTP Code: 

This is how I try to connect, it fails with "New-SSHSession : No suitable method found to complete authentication (keyboard-interactive)"

$key = C:\temp\test.key
$IP = "10.10.10.10"
$cred = Get-Credential
New-SSHSession -Computername $IP -KeyFile $key -Credential $cred

Any thoughts on how I can pass the OTP code for a proper auth?
I have the OTP token as a variable. I've also tried to set it as the password for the $cred, to no avail.

The issue names no source file, test, or entry point. Start by reproducing the public-key-then-OTP flow described through PoSH-SSH and SSH.NET, then trace the keyboard-interactive authentication path; done means a server requiring both methods can complete authentication with the supplied OTP.