Collaborator with Developer access is unable to manage keys or modify collaborators.
According to your site "Developers can modify the code or rebuild the app. They may delete the app, manage signing keys, or add other collaborators."
I've also tried unlocking one of my keys, but it doesn't show up for the collaborator.
Also, the collaborator shows up twice:
some@email.com Developer Edit Delete
some@email.com Developer (pending acceptance)
The email is obscured for privacy.
App ID: 948817
According to your site "Developers can modify the code or rebuild the app. They may delete the app, manage signing keys, or add other collaborators."
I've also tried unlocking one of my keys, but it doesn't show up for the collaborator.
Also, the collaborator shows up twice:
some@email.com Developer Edit Delete
some@email.com Developer (pending acceptance)
The email is obscured for privacy.
App ID: 948817

Statens vegvesen Vegdirektoratet
Regardless, I am now wondering if it's possible to transfer ownership of an app?
Amir
The feature of transferring ownership not yet available (not planned). You might want to file for feature request here:
https://github.com/phonegap/build/issues
Cheers!