Slipped on some ice in the parking lot and now I'm getting the runaround

So here's my situation and I'm curious if anyone else has dealt with something similar. I work at a shop just outside of town and last month I was coming in for my shift, walking across the parking lot that my employer owns, when I hit a patch of black ice that nobody had salted yet. Went down hard and ended up with a fractured ankle. I reported it right away and filled out all the incident reports, but now the insurance company is telling me they might not cover it because they're saying I wasn't "on the clock" yet since I hadn't clocked in. I was literally walking into the building to start my shift, in an area my employer controls, and I've always heard that still counts. I've been doing a lot of reading and it seems like this is one of those gray areas where having someone who knows the ins and outs makes a huge difference, so I'm considering reaching out to a New Paltz work accident lawyer to get some clarity. Has anyone here successfully fought a denial for something that happened in the parking lot right before your shift? I'm getting bills from the urgent care and I'm really hoping I don't get stuck paying them myself when this happened because my employer didn't bother salting the lot after that storm.