La isla de los hombres peces

I saw this movie on television as SCREAMERS and loved it. I heard an interesting story about this film. When Roger Corman released it to drive-ins in the summer of 1981, his trailer department sent out an advance trailer which was not actually footage from the film. It was allegedly footage of a naked woman being chased around a laboratory set by a monster. During the film's opening at drive-in's, irate customers complained the did not see the movie they paid to see. Theater owners called Corman and said their customers felt ripped off. So Corman had to run off copies of the footage, and send the positive film to theater owners to splice into the film themselves. Since the footage was never part of the film negative, it has not appeared in any video, DVD or television broadcast. Has anyone ever seen this footage? Anyone who saw this film at a drive-in in the summer of 1981 remember this?