Probably a beken chip, should be easy enough to flash OpenBeken using the pins if they're exposed
You can usually take over tuya devices if you sign up for a developer account and go some sort of verification process, it's pretty easy, sometimes it's possible to get a token for local control (tuya-local)
That’s what we do.
Played around with them a while go.
Found out you could do code execution while staying in the bootloader mode.. lol.
But wasn't able to extract the keys I wanted.