Well the current Yoshi is definitely male. Female casque and coloration is nothing like the picture of that male. The old Yoshi is unidentified until I see a hind foot clearly. That little nub/wart/growth of a spur is there from day one of a veiled baby and if you look for it, it is noticeable.
Besides finding [your] cham after so long, I'm not at ALL surprised that it survived a Texas summer. They are from extremely hot regions of the Middle East, and the humidity is famous. They survive on condensation in the cool mornings, bring their bodies up to a good temp to get muscle action and digestion, then head into shade to estivate during the heat of the day. I used the internet to follow daily temp/humidity of Yemen for a while. Eye opening.
Another part of me still thinks you may have found a different Yoshi. This also would be very very cool! How many lost veiled chams could there be in your area?? Further, I wonder how large Yoshi was at the point the escape was made, and the subsequent size of the found Yoshi.
This is a story for the books!
Tyg