Is Gringotts in the center of the Wizarding world?

Yeah it does

It is in the center of Diagon Alley on the Universal side.

There is a Gingott's in both parks

Yes, and no. It isn't in the Wizarding World in Islands of Adventure. It's in Diagon Alley in Universal Studios.

Sure is and with a fire breathing dragon on top of it.

Yes

Yes and it had a dragon on top