I see nobody has responded here, I did a little web search on the subject, and there appear to be several organizations (I assume many with local chapters) that are dedicated to helping handicapped people get out on the water with kayaking and fishing. Perhaps there is a local fishing club or meetup group in your area. This forum is very big, if you let everyone know where you live, there are likely Hobie Guys in your area who look for any reason to go out. I think Hobie (and Hobie Fishing) sponsors a lot of local events around this subject.
Just thinking about it, by adding a spring return (or a rope handle attached to one pedal that you can pull back with your hand to one of the pedals, you can likely successfully still pedal around just fine (just tryin to help here)
I have a Tandem Island and have both sets of pedals rigged so when I pedal both pedal sets operate, by adding two 3ft ski rope type handles to my mirage drive pedals I can use both my arms and my legs to operate the mirage drive (or drives) ( I'm kind of a human power/energy conservation nut). I keep my hand drive rope thingys in my mesh pockets, just in case my legs ever get too tired. (Hey it works). My kayaking is kind of my exercise program and I try to pedal my crazy boat at least 15 miles a week. However I don't fish at all.
Hope this helps you ( the ski rope thingies)
I'm just speculating here but I suspect if you add the H-bar system to your PA you can probably hoist yourself into the boat at waters edge, a tilting trailer with an electric winch may help with launch and retrival, of course some assistance will still be needed, but hopefully I'm giving you some good ideas (just tryin to help)