Here is a super rough draft of the steal fix, it checks party ID (formation screen number) instead of ENTD flags. I haven't tested it at all so it may work perfectly or fail catastrophically. I'll test it next chance I get but if you play with it let me know how it behaves. thanks!
Disclaimer: may cause freezes, keep a backed-up ISO
Edit: Testing it now, it doesn't work FYI, i messed the code up a little bit, stand by