Brian: rubber boats are mostly made of a material called Hypalon; very heavy and very expensive.
The problem with a branch penetrating an RV roof (any RV), is the roof structure may be destroyed (if the roof is made from welded aluminum, requiring an experienced TIG aluminum welder, repairing it is going to be a very very tricky and skill-filled endeavor).
If the roof's EPDM (rubber) is torn, then get an RV-sized roll --the roll has to actually be wider than the RV roof, and must be seamlessly(!) applied in one long piece. This is a VERY specialized job, requirng sealant that is compatible with EPDM. EPDM may or may not be used these days as much as TPO for roofing commercially (on buildings) in Mexico, so it may be difficult to find a large enough roll of EPDM material already in Mexico. Also, if your roof decking is destroyed (probably likely), you will have to re-deck the damaged roof section.
You may want to do a large temporary patch, until you can get the right materials, sealants and decking and find the right Mexican expertise to do the job technically correctly. If your camper roof has damaged aluminum structural members, you'll have to find the aluminum stock somewhere in Mexico, too.
The RV manufacturing industry uses something called white-on-black EPDM membrane, typically in the 42 mil thickness (a much more robust white-on-black is 60 mil, and is rated: walk-on). You can order it as 15 x 25 feet, up to over 40 feet long. Carlisle SynTec is the manufacturer (800.479.6832 in Carlisle, PA). I would call them, and inquire on who is carrying the product in Mexico in your region (this stuff is probably used in Mexico). Here is Carlisle's web contact info,
here-->Good luck,
S-
