Fold would have been correct pre-flop and post-flop at these levels.

So it is easier for others to follow the money:

20/40 Blind money in
4x Raise with OP calling
380 in the pot.
Post Flop - Original raiser brings it up another 380 (720 Total).
OP comes over the top for an additional 1060 (2160 in the Pot)
Raiser Calls for a Pot of 3220