Fiberglass shower pan

[Goldenstar38]

The head in my boat has a beautiful teak grate flooring covering a fiberglass "L" shape shower pan. I just fixed the faucet and used the shower for the first time. That night, I noticed that part of the shower did not drain, and left a 3/8" puddle of water. The head is "L" shaped, the larger area drains well, where the shower drain sump is. The short end of the "L" is right in front of the toilet. This area is not draining. I can see that if at sea, the motion of the boat would splash this away. In the marina, it bothers me. Would it be acceptable to fiberglass a panel in and slope it down to the main drain area to allow this area to drain? There is a grate there with some clearance to spare. I cannot get under the shower pan in this area. I'm way too big.
Please forgive my longwinded question. Just wanted to try and fully explain my issue. Than you.

 

[HopCar]

Before you commit to something permanent, why don't you experiment with something removable and see if your fix will work?

Could you fill the low spot with epoxy putty?

Would the work be visible or hidden under the teak grate?