Thanks for the question! To my knowledge, the fossils of an individual organism have never been found split between two continents. I cannot think of any reason why this would be impossible, although there are reasons why it is unlikely. When a continent splits into two continents, a rift between the two new continents forms and fills with hot magma rushing up from many miles deep in the ground. The rocks nearby the magma get "cooked" and sometimes melt completely.

Any dinosaur bones in these rocks would be destroyed by this heat. In addition, the splitting of a continent causes rocks to stretch, crack, and move around relative to nearby rocks, processes which are also likely to destroy dinosaur bones.

To summarize: given ideal conditions, there is no reason why it is impossible to split in two and preserve a single dinosaur skeleton on multiple continents; however, this is highly unlikely and I know of no found examples.