Question

Maran writes in section 184, paragraph 1: One who ate in one place must recite the blessing before leaving that place. (Gloss: See above, section 178.)
And if he left his place without reciting the blessing, if he did so deliberately he must return to his place and recite the blessing, but if he recited it in the place where he remembered, he has fulfilled his obligation.
Gloss: And this is specifically according to the view of Maimonides, but according to the Rosh, who holds that even if it was unintentional he should preferably return to his place, if it was deliberate then even after the fact he has not fulfilled his obligation (Tur).
And if it was unintentional, according to Maimonides he should recite the blessing in the place where he remembered, whereas according to Rabbeinu Yonah and the Rosh, he too should return to his place and recite the blessing:
Did the Rema mean to rule this way, like the Rosh, or is that not necessarily so, since he did not write “and so is the main ruling,” or “and so the custom is”?
Thank you