Northern Beardless-Tyrannulet

Thanks for any help with the ID of this small bird found in the Yucatan Peninsula, Mexico.
I'm sure is one of the small grayish flycatchers. Looks to me an awful lot like the Gray Flycatcher (bill specially). But I'm not sure as there are so many similar, and it would be slightly out range in particular for summer breeding when it was spotted. And there may be some Caribbean or South American ones that are not in my references.