YES
Certified

Tool output:
YES
(0
 (rr2 (comp (step (0-)) (step! (0))) 1 0)
 (rr2 (comp (step (0-)) (step! (0))) 1 0))
(1 (rr2 (step* (0)) 1 0) (rr2 (step* (0)) 1 0))
(2 (not 1) (not (rr2 (step* (0)) 1 0)))
(3
 (and (0 2))
 (and ((rr2 (comp (step (0-)) (step! (0))) 1 0) (not (rr2 (step* (0)) 1 0)))))
(4
 (exists 3)
 (exists (and ((rr2 (comp (step (0-)) (step! (0))) 1 0)
    (not (rr2 (step* (0)) 1 0))))))
(5
 (exists 4)
 (exists (exists (and ((rr2 (comp (step (0-)) (step! (0))) 1 0)
     (not (rr2 (step* (0)) 1 0)))))))
(6
 (not 5)
 (not (exists (exists (and ((rr2 (comp (step (0-)) (step! (0))) 1 0)
      (not (rr2 (step* (0)) 1 0))))))))
(7
 (nnf 6)
 (forall (forall (or ((not (rr2 (comp (step (0-)) (step! (0))) 1 0))
     (rr2 (step* (0)) 1 0))))))
(nonempty 7)