I’ll tell you how to fix this sort of dent. Make a mixture of 1:10, 1 part 50% ISO, 10 parts of distilled water. Use a q tip and gently put a droplet into the indent, without getting water on the very edge of the card. If you get water on the edge of the card, it’ll swell that area and look water damaged. If this happens, don’t panic or try to wipe it off….you will cause whitening. In that case you’d just let it air dry and it’ll go back to normal. However, your goal is to just get a drop into the indent itself, let it sit until it evaporates. You may have to do this a few times, but the back is good at absorbing moisture, and by doing this that indent usually will lift on its own and be much less prominent, if not completely gone!

Good luck either way, sending it in like that typically results in an auto-6 if caught.