Actually, yes, I do have welding experience. My father ran an automotive and machinery restoration business and I've welded, silver soldered and brazed parts for valuable antique vehicles as well as having done custom automotive body and fame work. I also made custom knives, both art and working pieces, and have a decent understanding of metallurgy. I have used JB weld numerous times for a variety of purposes and as I stated, the JB Weld putty or paste is nothing more than epoxy with a metalic filler. Epoxy can and has been used to build bicycle frames, carbon fiber bikes are entirely fiber reinforced resin. That is a far cry from sticking two pieces of structural aluminum together with epoxy putty.
The people here are trying to help you. If you don't think we know what we are talking about, feel free to take your question to the framebuilder's forum and ask it there.
There are many welders who work with aluminum, both of my stepsons are experienced welders, one of whom worked for an aluminum truck box manufacturer as a lead welder and the other works at a company that contracts to produce military equipment. Both are qualified in variety of specialty welding applications, including aluminum. Can an aluminum frame be repaired, sure, but you would not only have to get the joint welded, you would also have to stress relieve the frame to prevent brittleness that could lead to later cracking. As mentioned, you probably have a warranty claim for a new frame that will also be under warranty. That goes out the window the second anyone else tries to weld or glue the frame back together.
Do what you like. Good luck to you.