I know escorts who just can't commit to specific acts like rimming by text because they don't know how the client looks, his hygiene, chemistry, etc..
Also some may not answer direct questions because they don't want to be too explicit by text. Could it be possible that you simply assumed he consented to a list of to do things?
I do agree with you and everyone else in this thread that the escort is getting paid for his time. I never liked "a la carte" escorts, dealing with them feels like a bazaar.