Sorry to hear about this. I have that exact same MH model and year.
My dealer was so pathetic, I finally had an independent shop do our warranty repairs, and FR reimbursed me for labor. They quickly sent parts directly to the shop.
I found out once I bypassed the dealer, that they never did put a claim in. They were waiting for me to bring the RV to them, even though we already did that once before they claimed to be waiting for parts.
The independent shop had everything resolved in days. I wasted months with the useless dealer that did nothing more than jack me around.
Just to be clear, our issues didn't involve the slides. Hard to tell from the pics, but those teeth look like cheap pot metal. I can see if anything falls into that track, it's gonna be a problem.
Please be sure to let us know how this ends up.
2020 Sunseeker 2860DS