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Sorry to hear freeing the latch has been a problem for you. The latch is designed not to be able to come out so sharing that part would mean you need to file it down post printing to enable it to fit... which would also mean it can come out again. Happy to send the latch as an .stl by email if you want. If so please message me your email address.
I suspect you can free the current print. The latch will be surprisingly strong if it's PLA. If you run a craft knife along the edges of it you can usually free the minor parts that are fused with a bit of wiggling. Chances are it is very little and the problem is just a lack of leverage to break it free... it's worth a try.
Usually these should print with no such issues if the file is precisely sliced and printed on an accurate machine with quality filament. However, for future prints you can avoid this by uniformly scaling the signs up 5 - 10% which will increase the clearances.
I hope this helps.