Yeah, I thought too. But I found something in the 1994 homologation paper (page3), which is disturb me. (In the 1995 homologation paper it is not in.)
I tried to search for infos, I only found that the homologation based on the "155 Silverstone" edition. It is hard to find, but I think only the Q4 has 4WD for street. And the Silverstone edition was FWD.
(But RWD behaviour is definatelly wrong for the physics of the F302's car.)
Ohhh... And don't forget the 155 GTA which was run in the Italian Supertourismo Championship (CIVT) in 1992, it was 4WD too!