Her task was to do half-amateur brain surgery on Jigsaw to attempt to remove his brain tumor. This means, amongst other things, she had access to plenty of towels and rags.

Well, the shotgun collar was apparently something of an open design, meaning she could have easily gotten behind Jigsaw where he couldn’t see her, wrap towels and/or rags tightly between the firing pins and the shotgun shells, and just walked away.

Hey, buffer/block the firing pins, so what if the trap triggered, the shells wouldn’t have went off…