The risk is that somebody will push in the wrong button one day, and they'll close the door behind them or the wind will blow the door closed and there won't be a way back in.
I can't wedge anything in tightly enough to keep the correct button down -- the gap between the button and the rest of the plate is as thin as the period at the end of this sentence.
I'm reluctant to use any glue unless I know it's a) permanent and b) not going to flow in somewhere it shouldn't and screw up the regular latch mechanism. Can someone recommend something safe to use?
I'd like to avoid taking out the whole plate if there's a 3 second fix. There are already two deadbolts on each door so I'm not worried about needing the security.