It’s a fun joke, but the main reason the second invasion failed was because of a strong defense(and a typhoon).

The Japanese had built up defensive walls and put pylons in the river to prevent boats getting inland. And when they took over an island which they held for about a month. There were counterattacks that forced them to retreat to an island even further out. And the Japanese kept doing night-time raids on the fleet, constantly keeping them away from the mainland until typhoon season.