heres a cheap and cheerful option.. cut the wing in half down the join, take the end template and make 4 new ribs, use these to make a new flat center section with highly leaned in edges, 2 ribs on the fuz, next 2 are leaned in ( they have to be taller to account for the lean ) so that when you mate up the old wings you have the correct dihedral. Of course the section should have a new brace running all the way through it and into the old wing "tips". the old brace half's can be removed with a heat gun and a screw in the brace with much pulling, either that or get a drill out followed by a needle file to make a new slot.
I did something similar with a glider, only my center section was a solid balsa block, and it wasn't because i made a mistake