So I also tried to go for the Chosen One ending and landed in the same situation as above.
The thing is that this was as a Grifter -> Merchant. I was
told that it is possible to recognize the prophet as a grifter and was hoping for some interaction there and possibly bypassing the bug by getting his vote or whatever, but I just get ignored. Shame, since it was the only time I got to see him during that playthrough.
If you're already doing a pass on the CO ending, maybe add something there. Getting his vote and/or hilariously revealing both of you as con-men.