I wondered about the above picture on the left with the Maltese Falcon.
https://deadline.com/2021/04/felix-silla-dies-cousin-itt-on-the-addams-family-tv-show-was-84-obituary-1234737466/
One role where he could be seen was as the villain Litvak, who took on George Segals Sam Spade Jr. in The Maltese Falcon sequel The Black Bird (1975).
Mystery solved! Apparently the movie stunk, which is too bad. Another interesting article:
https://www.hollywoodreporter.com/news/felix-silla-cousin-itt-on-the-addams-family-dies-at-84
A year later, he worked in the Gig Young-Shirley Jones comedy film A Ticklish Affair and appeared on the Bonanza episode "Hoss and the Leprechauns," and in 1965, he was in "The Cage," the 1965 first pilot for Star Trek.
Silla's size allowed him to stand in, double and/or play youngsters, as in Planet of the Apes (1968), Demon Seed (1977) and Indiana Jones and the Temple of Doom (1984), and he did stunt work in The Towering Inferno (1974), The Hindenburg (1975), E.T. the Extra-Terrestrial (1982), Poltergeist (1982), The Golden Child (1986), Howard the Duck (1986) and Batman Returns (1992).
His big-screen résumé also included Point Blank (1967), The Kentucky Fried Movie (1977), The Brood (1979) and Spaceballs (1987), and on TV, he was a regular performer for Sid and Marty Krofft on H.R. Pufnstuf and Lidsville
The article goes on, with many more roles mentioned. ...Wait a minute. Felix Silla was in ST: The Cage?
https://www.startrek.com/article/catching-up-with-the-cage-talosian-felix-silla
Short article about his appearance in the episode as well as an interview, well worth the read:
I'm fully retired. I retired in 1996. I did my last movie in Romania and then I just retired. I gave it up. I got my pension. There's not much work left in California. As a matter of fact, not too much work now, because little people, there's so many little people and not enough work for everybody. So, I gave it up, and in 2003 I decided to move out of the San Fernando Valley, and I moved to Las Vegas. And, yes, now I do a lot of conventions, signing autographs, making appearances. I enjoy it. I get to see all of my fans and I get to meet some new ones. I'm having a lot of fun, traveling, a lot of traveling. Ill be in Las Vegas for the big Star Trek convention. I live here, in Vegas, so its an easy one for me. [snip]
When I do these shows, everyone says, "You're a part of my life" or "I grew up with you." I love to hear that. I made a living, I worked with some very talented people, and I also made a lot of people happy. Ive also got my family
(his wife, two daughters, a son and five grandchildren). So, Ive got plenty to keep me busy. [more]
Yes, he did make a lot of people very happy. It sounds like he had a good time doing what loved and was very happy himself, which makes me glad. What a long interesting career (and life) Felix Silla had.