120 film is not as fragile as you think. I've opened the back and found out that I didn't wind far enough, saw backing paper still loose and thought, "OMG, I ruined it!" but I developed it and it turned out just fine. In fact, my scarf once caught the release slider on my RB67 and opened the back when I was on frame 9/10 and the first 5 frames were perfect, some fogging on 6 and 7 and 8 was pretty much toast. That little piece of sticky paper holds it just fine.