Since they were all filmed on nitrate stock and back then no preservation methods were observed, the films either disintegrated over time or more preseumably were lost back in the 70s (60s, maybe?) when MGM had a huge fire and lost hundreds if not thousands of original negatives. Chances are though at that point these would have been half turn-to-dust anyway.
Therefore, these are considered lost since no known prints exist. Nitrate was a highly flammable film stock that studios used back in the day.. thats why so many silent films are long gone as well.
Chances are if anybody did have a copy of either of these three films, they'd be unusable now. A similar thing happened to Soup to Nuts, but there's a nice little story here on the Board as to how that was saved.
I'm sure BeAStooge will be a lot more thorough, but this is the general idea.
