Do I have to tell my insurance choice if my remark reduced a grade

I was accepted by my insurance but missed my firm. My teacher thinks something went wrong with the marking for two of my papers and has requested transcripts. However, I am only one mark above the B boundary and am hoping to get it remarked for an A. So if it goes down to a C after remarking, I will miss my insurance choice too. Will i have to inform my insurance choice of this and will it cost me my offer?

I am only one mark above the B boundary and am hoping to get it remarked for an A. So if it goes down to a C after remarking...

the chance that you get bumped up to an A is approaching 0%, and the chance you get downgraded is high

unless your teacher notices a mistake in your paper's marking, just leave it as-is

as far as i know, if you get it remarked and magically it goes up to an A, you won't be retroactively accepted into your firm choice anyway because they will have given that place away already most likely

Likely yes. Insurance offers are still conditional, so failing to meet those conditions could cost you an offer. Unless you email them directly however, pre-remark, you won't know for sure. Being only one mark over the B boundary, it's highly likely a remark could push you into a C category too, so be very sure you want to chance it first.