Hi

I've brought up Safiya's loyalty (to 83), so she got the "Devotion of the Red Wizard" feat and associated bonuses.
I am sure my character was supposed to get a similar feat (and some bonus) as well - but it didn't happen. Anybody knows why?

I have also recruited Gann and brough his influence using a script to test it - and, again, only he got the feat.

Has anyone encountered this issue?

Just talk to her. You should get the corresponding feat after that. I don't know if it'll work when you raise the influence through a script, because it could lead to skipping some dialogues.

Doesn't work. No new dialogue is available (Safiya's influence was raised via dialogue).
Does the story need to reach a certain point before this bonus is available? Or should I get it as soon as I manage to get enough influence? Safiya's influence is really easy to get, so maybe I just need to be more patient?

I don't remember unfortunately. I presume that it should work once you achieve enough influence, but try to wait a little and progress the story. Maybe it'll help.

Surprisingly, in a new game I had no such issues. However, to get the devoted (i.e. the second) feat from Safiya, I had to wait for act 2 to start.

Surprisingly, it is possible to get Gann's influence to above 50 in act 1 - and the loyal conversation references the curse, despite it never having been mentioned before. :)