The submarine can be skipped by doing the tongue glitch in this level. To perform the trick, you first need either a pow block, or a big egg. Big eggs are recommended as there is no known way to consistently get a POW block. See below for setups on keeping big eggs from 2-7 into 3-3.
In the 2nd screen of 3-3 with a big egg, grab an enemy, throw the big egg into the air, and spit out the enemy right before the big egg lands. This will activate the tongue glitch.