There are several LOR threads going! It’s a sign they want a little more info from you. It does not necessarily mean you are borderline - they can also be kind of random. Do submit - I thought they were asking for 2, but I don’t know what your email tells you. My D had to do it last year, and I don’t think she was borderline. She was accepted and is attending. Upshot: get whatever LOR’s they are recommending and submit them.