I think I watched a documentary on this, not sure if it was the ISS but something like this already happened and they literally duct taped the hatch closed as a precaution.
Worse case scenario I imagine the procedure would be to duct tape the person up so they can’t do anything stupid.
It was a shuttle mission https://arstechnica.com/space/2024/01/solving-a-nasa-mystery-why-did-space-shuttle-commanders-lock-the-hatch/