Need some help to remove tris on a 3D model

Hi, if there's someone here who could help me..
my problem is that i'm working in a ship (thousand sunny from the anime One Piece) and last night i was working and i forgot saving last 4 hours, and when i exported it, becuase i wanted to send it to zbrush from maya to try something, i did it with the option of triangulizate...
so now, i have all the mesh triangulizated, and i don't know how should i remove all the tris, i've tryed in max and maya the Untriangulizate option, but it never works properly, or at least i don't know how to use it properly.

Any tips? removing all the edged from the tris is pretty imposible, it would require to many time, the other option would be start again from the last save...

i though maybe in a sculpt software like zBrush, i could subdivide it to million polygons, and then try to somehow delete all triangles, then do a low mesh but i don't know how should i do it.

All kind of help is really apreciated, and sorry for my bad english

Thanks!