I don't think we use "probably" in an affirmative sentence in Present Simple. We usually use "probably" with "will" or Present Perfect. "They probably accept" sounds weird. Present Simple here expresses a fact, not a probability: either they accept your choice or they don't.
It really is the main translation. If you encounter this sentence another time, could you write "They probably accept your choice" again and if it won't be accepted, make some print screen and post it here? Because that sure seems very weird, it was checked in the Incubator as well and we don't see any reason for this problem.