Learning global access group - transfer ownership?

Summary:

Raised an SR but was closed out in favour of self-serve, and I've had no reply to a comment in two weeks. Desperately need an answer on this please.

To my knowledge we have two Learning Specialist type roles set up in the system, one for global administrators such as myself, the other for local learning admins with an AoR constraint.

A local learning admin has moved on, and we've used HDL to reassign their courses to a new user. However, the new user is unable to see the global access groups set up by their predecessor.

I can see them, which suggests an access issue.