Dimmer Switch Not Switching Sometimes

So I have a 2 gang box (old, metal) that has 2 new 3-way LED dimmers (the style with the paddle switch). The dimmers together are a very tight fit in the box, but they did fit mostly nicely after I worked the metal tabs of the box slightly flatter on the sides.

The weird thing is that the first time I put the plate on and turned the breaker back on, one light was off (the one that’s wired as just a single pole, not a three way), I flipped the switch, it turned on, good. I turned the switch off, light stayed on, but the dimmer slide would control brightness. So I took the dimmer back out of the box to test my wiring, checked it again and it was controlling it properly.

So I put it back in the box, plate on, and now it’s working like it should be.

So, it’s fine, but weird. I’m guessing something inside the switch bound slightly and prevented it from breaking contact because it was too tight? Any idea what happened here and if I should double check anything or just leave it alone now that it’s working?