Potential Unleashed is not a super state or any sort of transformation, it is a "super base form". All of his dormant power was drawn out and amplified beyond its limits by Elder Kai, and Gohan
just has that power now. It is a similar situation to Goku infusing the power of the Super Saiyan God into his body.
Only the Super anime "portrays" it as a transformation, and we do not back-pedal off of Super, if memory serves me correctly. There are two separate sequels branching off of the original manga, so the Wiki avoids using either of them to powerscale Z characters.
Also, in the manga, Vegito transforms right off the bat, seemingly out of a sense of urgency. In the anime, though, Vegito is mega-confident and pummels Buu for a good thirty minutes or two before transforming. These two scenes are not at all compatible, so using the anime to support the manga in this instance