Trans was supposed to be able to handle 750rwhp no problem.
When find a company that will back that up let us know. They can claim anything they want but unless they back it up with free fixes it is nothing but hot air. At 750 HP you are well over 1000 ft\lbs and that is what will kill ANY light duty transmission. Not a matter if, just when and that has a lot of variable factors.
It depends on what is actually happening to make it fail whether there are parts to make it work better. Even just burned OD clutches can have multiple sources form not enough pressure to too little clearance.
It will also depend on how you are using it. If you are trying to GCVW tow at 30k or better never will fix the issues, the parts are just too small to handle stress of towing in OD. Not sure what toi advise without knowing a lot more about the truck and how it is used.