RZR 800 Rear Sway Bar Missing? Safe to ride?

Hey guys. Just got on a weekend trip and my buddy noticed his rear driver’s side sway bar missing from his 2013 RZR 800-S. His passenger sway bar is still attached.

Is his weekend toast or is it okay for him to ride it easy? Thoughts. Will he do further damage if he rides easy? Is sway bar for high speed stabilization?