anguswilly
+1y
It can be repaired but in order to provide proper safety, you will ned to adhere to proper auto body repair techniques.
You may want to cut the patch much larger than the affected area and install it on the outside (bottom) of the floor so there is less chance of the patch pulling off in an accident.
Make sure you clean the area to be welded 100% of any rust, paint or undercoating - and make sure your "friends" can do REALLY good welds, I would consider spot welding it in even, or drilling holes through the top panel so you can weld it from the top as well.