The man is standing upside down on the bottle, with hands on the ground.
A man might fall off the bottle.
There is nothing in sentence 2 that cannot be inferred from sentence 1. It is natural to assume that a person may fall.
exists e1 s1 s2 x1 x2 x3 x4.(n_ground(x4) & n_bottle(x2) & n_man(x1) & on(e1,x4) & with(e1,x3) & n_hand(x3) & on(e1,x2) & a_down(s2) & Manner(e1,s2) & a_upside(s1) & Manner(e1,s1) & Actor(e1,x1) & v_stand(e1))
exists e1 p1 x1 x2.(n_bottle(x2) & exists e2 s1.(Time(e2,x2) & a_off(s1) & Manner(e2,s1) & Actor(e2,x1) & v_fall(e2)) & Topic(e1,p1) & Actor(e1,x1) & v_might(e1) & n_man(x1))