that very much depends on how recent these profiles are, and how closely related to them you are. If the abandoned profiles are public, either having been made so by the manager, or because they are for people born before ~1850, then a Curator like myself can complete them for you.
If you are referring to Leora Smith, then the only public profile in her tree is for Yitzchak Moshe a great-grandfather. There are 28 Geni users within her Family-Group, they should all be able to complete merges on her private profiles. With a little sleuthing, you should be able to find their profiles and contact them.
These are all profiles after 1850, mostly for living people. I'm not sure how to do this sleuthing; for example, for this "Nili Tock" record the only manager is Leora Smith. She did not accept collaboration request so I cannot se her tree. How should I proceed? This is an obviously-correct merge requests for abandoned record.
If Geni recognises that Bram is Leora's second cousin, then Bram can access Leora's private profiles. Collaboration only affects public profiles, not private profiles.
In general, if two people are in the same family group (4th cousins or closer) they can always access each other's private profiles [except claimed profiles and perhaps those of minors]