Other users can't load my prebuild

Bug description

DrupalPod repo is based on the fact that I run the prebuild ahead of time, and all other users open the workspace and ready to work.
A user reported that when they open a workspace with DrupalPod, instead of loading the prebuild, when opening the workspace init task starts running.

Steps to reproduce

Open https://github.com/shaal/gitpod--prebuild-for-other-users in Gitpod by following this link -
https://gitpod.io/#https://github.com/shaal/gitpod--prebuild-for-other-users

There's a 60 seconds countdown timer that already ran in prebuild, if you see the countdown in your workspace, it failed loading prebuild.

Workspace affected

No response

Expected behavior

When a prebuild is available, any user who open the workspace should get the prebuild.

Example repository

https://github.com/shaal/gitpod--prebuild-for-other-users
https://github.com/shaal/DrupalPod

Anything else?

It seems to be inconsistent who gets to load prebuild and who doesn't.
@rfay can load prebuilds of my repos, @tyler36 cannot load prebuild of my repos.

Tyler36 couldn't load the prebuild for https://github.com/shaal/ddev-gitpod, after I confirmed the prebuild loads for me.
I asked him to fork my ddev-gitpod repo, and generate the prebuild in his Gitpod account - https://github.com/tyler36/ddev-gitpod
He was able to open his fork and it loaded the prebuild for him.
I tried opening his fork but it did NOT load the perbuild for me.

Start by reproducing the behavior with the linked gitpod--prebuild-for-other-users repository and compare workspace creation for the listed users and forks. Check whether the available prebuild is selected instead of running the init task. Done means other users consistently load an existing prebuild, including for the DrupalPod and ddev-gitpod examples.