Any pictures of said nanner plant? From what I'm reading personally I wouldn't have tossed it. late flower nanners are from environmental stress and any seeds should be S1 feminized but would have needed the next 4+ weeks to develop into fully viable seeds if they weren't sterile to begain with.
It is nanners and balls that develop along side female flowers at the same time and start opening around day 21 of flower you don't want, That is the bad genetic hermi trait for the garbage can and if left unchecked will pollinate a country mile, just think shitty seeds for days and pissed off neighbors especially growing outdoors.
Bigger problem I'm reading is you saying it's "only happened a few times before" something probably could be corrected in the environment, i.e..light leak, temp swing, red power strip light......
Cbga is the chemical precursor to most know cannabinoids, thca, cbda, cbca...., Meaning it is found at a earlier stage in maximum quantity. if ( I think you should) you keep it the Cdga would be decarb-ed at my house ( i believe the vaporizing point of cbg is186f) in doing so should activate and could possibly improve the other underdeveloped cannabinoids All of my earily clippings, leaves, pinching, go into a bucket for salve with later harvested root, bud, keaf. leaves,..getting the idea here.