Safe or replace? Never crashed or dropped, but found large cracks

For context I've been racing since I was 4, and I know how important a helmet is I emailed the brand and called but it's been 4 days and I still haven't gotten a response. This helmet was a replacement for one I crashed in and is now about 3.5-4 years old. I haven't crashed in this helmet and as far as I know I've never dropped it. My last helmet was replaced because of smaller cracks than this so I'm really not sure what the route is here.

I'm on a time crunch, leave for Whistler in 2 days and need to figure out if I've got to buy a new helmet when I get there or not. My guts saying replace it, my dad's says it's fine. I'm leaning towards replacing it.