Grey/green on pork ribs’ fat before best used by date?

(I did already post in r/foodsafety albeit under a different, less-karma account to no response yesterday, just hoping to get some insight from a more active sub – sorry, I know these posts are divisive)

I'm not familiar with pork and there's some weirdly new gray/greenish spots on the pork fat.

On Friday, Aug 1 2pm – had a pickup grocery order with a value pack of raw, country style (aka limited bones) ribs from a local grocer (with a meat counter). Best by date said Sunday Aug 3 (yesterday) so it's been almost exactly 48 hrs from purchase to these photos, cutting, and cooking them for chili prep. I don't often shop at this grocer.

Brought it home immediately, repacked it from the black Styrofoam wrap into zip bags then into my fridge. Some of the meat folded in half due to the bag orientation. Seemed perfectly fine then.

Sunday (photo time) I unpacked it to make hatch green chile chili.

Noticed some grayish spots on the top of some of the fattier ribs. Starting from the top, ribs 3 and 4 are the worst offenders (rib 1 isn't as significantly dark as the rightmost part of rib 3 and the crease in rib 4 and definitely seems the color is 50/50 because half was sitting in blood).

The ribs towards the bottom of the bag seemed more fine/less gray green, except for the one rib (4) that was folded over in half – that piece had a significant gray spot (IMO) comparatively, where it folded over at. I took a photo with flash as well (photo 4).

I still trimmed and cooked fully to use later in case it's fine. I noticed on the grayer spots that there were bloody veins nearby. Is it possibly some kind of bruise?

Photos: photo 1 is all ribs, photos 2 and 3 are of rib 4, photo 4 is of rib 4 with flash, photo 5 is no flash of rib 3.

Unfortunately I don't often cook with meat and so can't really identify a rotten smell or sliminess – all meat is 'slimy' to me, and it smells vaguely of vinegar/raw steak/maybe a little eggy but that may be the vinegar smell I'm associating with it.

The pink meat of the pork felt firm and fine and no discoloration on it (except where there were spots of fat). Not iridescent anywhere either. Literally was just on the fat and was pretty shallow when cutting it off.

I've gotten horrible food poisoning from (expired) cooked pork before so maybe I'm being overly cautious, but I'd really appreciate input from folks who are more familiar.

Thanks!