Low lighting sports advice

Hey y'all. So Ive recently become professional/paid after over a decade of just laying dormant so that I could build my life on other more steady income

Anyway, I have got myself a monthly gig that involves rodeo events in an outdoor horse arena. Last night I found out for the first time how bad the led stadium lights truly were. I've shot sports previously with stadium lights and in auditoriums but this was the worst I've ever seen. This is a very casual arena setup

I'm looking for advice on what I can reasonably change to be able to take profitable photos.

I use a D3. I was previously pushing it at Hi 2.0, 1/500, f/2.8 & jpeg fine. yes, I normally shoot sports at f/ 2.8.

Obviously at this point I was really really pushing it on quality. I dropped as low as I was willing to go on shutter speed. I normally shoot jpeg fine during these events for space saving. It's generally close to 5hour long event with no stopping, just heats back to back. This is a rodeo, with horses and myself in the arena. Flash is not an option

My first question, I dual slot 2 32gb cf cards currently. Would moving to raw files once the sun goes down help with the low light and grain in terms of post processing?

Or what post processing advice do y'all have?

Ultimately, if there isn't really a good tip y'all can give without me having to upgrade my body (which I can't afford to do currently), it's not the end of the world for me and I'd like to be told if there is no other option within the parameters of my D3. I get paid by the photo and it's extra income.

Thanks y'all