> Houthis have submarines? <
Maybe they could just borrow the one that destroyed the North Sea pipeline.
The Bab-el-Mandeb Strait is 16 miles wide and only 96 ft. deep. Doesn't take much of a submersible to go down 100 ft. Hydrostatic pressure at that depth is 56 psi (not much pressure). With Iran's help, they could build a undersea RPV very quickly to deliver explosives.
Also, there are cable landing stations all over the place that are vulnerable.