Might have been better ask in the frame builders forum. I'm not sure you got answers from anyone that really knows about welding or brazing tubes for bicycles.
If I had to ask the question, then I wouldn't trust myself to weld or braze it. The tubes used in bikes can be pretty thin. Nor would I trust just any welder. It's not just simply reconnecting the to ends of the fracture. Heating the tube to the temps necessary for welding and brazing always brings embrittlement as a factor to the immediate area around the fix. That means that the person doing the fix needs to know if the part experiences tension, torsion, compression, flex, etc so they can decide if an insert or collar is needed or if the entire tube should be replaced. So you might pay more for that knowledge than the bike is worth.
Or just simply have it welded by any joe blow welder and you might get lucky. But don't be surprised if they hit it with too heavy a rod and the metal heats up too much and melts completely and turns into a big hole.