This was not made specifically clear in the movie, or maybe I missed something.
Data remarked later in the film, that flying into the nexus causes ships to be damaged or destroyed when flying near the Nexus energy ribbon, this fact was reinforced by the opening scenes of the movie. However, Dr Soran obviously felt this got him into the Nexus initially and was also backed by the fact that all crew members of both ships destroyed in the Nexus energy wave were phasing in and out of time and space (i.e. they were entering the Nexus). Guinan herself experienced the Nexus, although it is vague if this was experienced from the SS Lakul and the SS Robert Fox ships caught in the energy ribbon from the starting scenes in the movie.
So as the question asks, however, 2 people experienced the nexus by being in a ship caught in the ribbon and data remarks flying into the nexus with the ship will only blow the ship up.