I've just had a look at the PAUSE user interface in regard to giving out module permissions, and I can confirm tye's finding that

• as a primary maintainer I can create co-maintainers but not new primary maintainers.
• as a co-maintainer all I can do is give up co-maintainership. In particular I can't create new co-maintainers.

But you say

PAUSE certainly supports more than one person being able to give out permissions to a module.

Are you saying it can be done, but not via the user interface?

Would you accept a patch that would allow e.g. co-maintainers to create other co-maintainers?