In Two Places At Once
I have seen this movie numerous times and am watching it again right now on Encore Westerns.
John Dierkes plays Jocko. He is the one married to Blind Nell. When Santa Anna offers to let the women and children be evacuated, Jocko wants to leave but Nell tells him to stay.
However, Jocko is also seen early in the opening of the movie riding in with Houston. Then, he rides out with Houston. If you watch closely, Jocko is near the head of the column and can be seen as Houston tells Jethro to "Stay temperate, Old Man." He is wearing the same clothes that he wears all through the movie.
So, Jocko left with Houston but then rides in with Bowie later. He was in two places at once.