Looks like you may have found something for the GoG team to follow up on.
So in essence the TLDR version, while GoG try to fix the problem, our work-around would be:
Jayvenpup: I have a successful repeatable situation for you to all check. This was the only way my wife and I could successfully trigger release gifts.
ALL steps must be followed exactly or it doesn't work.
In this example, you are Player 1 and the hired Pawn belongs to Player 2.
Step 1: Player 1 equips Pawn with anything they wish to send Player 2
Step 2: Player 1 sleeps
Step 3: Player 1 releases Pawn (only tried with giving a gift at release)
Step 4: Player 1 sleeps
Step 5: Player 2 sleeps
Step 6: Player 2 should receive notification that their Pawn has returned from helping Player 1
We tested this on both my game and my wife's and the above worked to the letter. If Player 1 does not sleep after every step before Player 2 sleeps at the end, it doesn't work.
If Step 2 is not done, any equipped items are lost, even if the rest of the steps are done correctly.
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Screenshot #1:
This shows the successful acquisition of Rift Crystals after Pawn return using the steps above.
Screenshot #2:
The Godsthrone Blossom was given upon release the day before when an Mage elemental buff was changed and the Rotten Scrag of Meat was gifted just now upon release. Not sure why two days worth of gifting was in this one because we have both rested many times between then and now. What we find odd is that the transfer of gifts/etc only seems to work if you reset immediately before and after the actions in the step guide above, resting earlier in the day doesn't seem to count.
Screenshot #3
The shield that Player 1 equipped to the Pawn didn't transfer through in the first attempt (Screenshot #2) for some reason, but we found that Player 1's rest after release seemed to trigger that transfer (Screenshot #3).
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Just a note regarding the possibility of offline mode corrupting saves: we discussed about how my wife's game did go into Offline mode at the start and my restarted game did not, so this was eliminated from our investigation as the above process worked on both of our games.
I've sent all my screenshots off to the GOG team and the above steps plus some additional notes.