Dingo, You're in the Keys. I wouldn't let this stop you from having a great time fishing on a great platform. KrazyIvan is right. There's a possibility depending on the various ways owners use their Fishpro, however the info posted usually contain very little information to make any conclusion.
The system is very simple. There are two lines coming into a jacketed exhaust manifold on the bottom. One is from the high pressure inlet between the impeller and nozzle. When the impeller is rotating, high pressure is created here and pushes the water to a lower pressure area. The other is the flush port. There is a smaller hose coming out of the manifold and goes up in a U shape that provides water into the exhaust. There a reason it's design that way.
If you are in high current, anchored from the bow, there may be a chance a high pressure system developed at the inlet from the flow, however any flow into the jacket will drain back out at the flush port. So you don't want to plug or leave any adapter on your flush port restricting flow.
I guess the other way to get water in is to anchor from the back in high current, but I just don't see any one doing this.
Another possibility is running an electric trolling motor at high speed against the current?