The L2Player fling arc looks true to L2. In particular, explosions pull upwards the lemmings
below the explosion, which doesn't make any sense physically, but L2 does it, too. Satisfying to watch.
L2Player can have lemmings flying backward, e.g., left-facers flung rightwards will continue to face left. L2 would turn these at fling-time, and lemmings would always fly facing forward.
Your exploder crater is the L1 crater. L2 has this only in Classic. All other tribes have the round crater. I don't know what L2 does under the hood, maybe it has 2 different exploder skills, or maybe the tribe affects the physics.
Touching walls or ceiling during flinging, I have no feeling for that in L2. Thus, L2Player's wall/ceiling collisions look good to me but I can't tell for sure.

-- Simon