From what I understand (I could be wrong), a bishop in India reinstated Father Gruner.
I still haven’t located any even purported statement of fact that Father Gruner was excommunicated or reinstated, for that matter. I do know of the incardination by the bishop in Hyderabad. I know also of the threat of excommunication from Cardinal Hoyos in 2000. That this threat came about in 2000 means that he could not have been excommunicated earlier. He has never been excommunicated, but relations with the Vatican have been perpetually strained.