I thought about this before, but I doubt it. Not having a quirk is one of the primary influences that shaped Deko's personality. That it then appears he actually had one, completely messes up his character. Putting aside the issue as of why his quirk then never manifested, this series is about how he went from a rookie to a real hero while mastering One for All. If he loses it, well it would be quite the coincidence that of all the possible quirks he would have one that's very similar to OfA. If he happens to have a mind reading quirk, well pretty much every training he ever did to master OfA has become pointless.
I also question the possibility of someone being able to steal OfA.