For all that have problems with "A date with the boss" because corsican just repeats his line and wanders off:
I tried everything with load order, deactivating XDI, resetai, recycleactor, different clothes, reload previous saves etc...
What did the trick was getting Apollo into the studio. For me he was still in "Fizztop Mountain". So i teleported him (click on him in console, walk back into the studio and type "moveto player". If Apollo is in the studio the dialogue will continue.
I really do not know what the problem with dogs is in this playthrough but Snoopy from Commonwealth slavers did not spawn either for a long time in the outdoor quests or in the whore house. I got the "scene" after sleeping but he was not there either. I saw him 1st time after already being at "animal friend 3" perk.
So to sum this up: Apollo needs to be in the room, if he isn't the dialogue will not continue!
If you can still find him you can teleport him via "moveto player", but you have to activate (click) him 1st in the console. This works btw also in other saves / new saves; teleport or go there, *click* him and load your studio save, then "moveto player".
I hope this helps. I do not know what mod (conflict) is causing this issues (maybe PRP and routing issues ?!), but just be aware of that issue.