I bet there was a lot of running (down the legs) when the Coastie opened fire on their engines!
Think of the skills required to hit a fast moving outboard engine while it’s bouncing away on the waves, from a shaking shuddering helicopter buffeting the the wind...
Looks like the shooter was using a .50BMG rifle. Serious skills.
And the smugglers probably shat themselves when a US helo showed up.