Maybe I can use one of my JB Welded fittings to do some informative destructive testing.
It boils down to whether the threaded part of the brass eyelet would pull out of the brass tube. It would be easy enough to solder the eyelet directly to the tube, but it first has to pass through a collar (stamped, plated aluminum?) and several other parts so that the actual location of the solder joint would not be visible while soldering. I would just have to trust that the solder if flowing into the joint.