Why wait around to find out if they failed the most basic part of the process?

That should be safe for this attack, I think it's says more about the quality of the product that this could even happen. It's not a mistake, it was a design choice. They've lost my confidence as a coldcard user.

I did it for peace of mind. Used their RNG + 300 dice rolls but moved it nonetheless

This post addresses that question: https://www.tftc.io/coldcard-rng-failed-move-your-coins Probably okay, but if like me, you can't remember the exact dice process then maybe prudent to move to a new seed. Just be slow and deliberate and don't panic I guess.

In that case it's fine - The 100 dice by themselves are 258 bits of entropy, so even if the system RNG is/was completely busted you still have a full strength key. This is assuming you did everything else right with the dice rolls by best practice (I.E used fair dice and so on).

IMO, there's no need to throw the baby out with the bathwater. Just don't rely on RNG for seed generation. Verify that your coldcard is processing dice rolls correctly (perhaps with several test cases); you should be fine. It shouldn't be surprising that if something was going to fall through the...

I’d definitely not sleep just hoping I was fine

Dice rolls and passphrases, quaint attempts to thwart NSA's bulk surveillance, courtesy of Bill Gates and Microsoft's backdoors.