First Hi an welcome
Second,
I am sorry you feel that the gliders couldn't care less whether or no you're there. Personally I believe gliders can bond no matter what their age or previous history is.
I currently have 3 rescues, a 4 year male I've had since October and 2 girls I've only had for about 3 weeks and a Leela who was a joey from a breeder. My male Simon is paired with Leela.
While it did take some time with him we are bonded it is different however than my bond with Leela. In some ways it's a deeper more trusting bond because I really had to earn it. In other ways my bond with Leela is deeper because it was easier.
The girls, were not there yet but we are making some good progress already. They didn't have names when I got them either and lived outside for the last year in some sort of aviary. I don't work and devote 90 percent of my day just to the gliders.
More information on why you think they aren't bonded to you would be helpful. There may be different methods that can help with whatever you are struggling with. Rescues/rehomed gliders bond differently than gliders from breeders who are properly socialized before finding a new home.
As for your need/want for one of you boys to father a joey, it's NOT a good idea. It's actually a better idea and would probably help your bond if you got both males neutered.
It's not recommended to breed rescue/rehomed gliders. For one thing you don't know their lineage so you could be inbreeding with any female you might get. I could add other reasons but the first reason alone should be enough to discourage you from allowing them to breed.
The other reasons would only guide you in allowing them to breed "safely" ( there is no safe way to breed unlineaged gliders) and I will not contribute information for you to be able to do that.
Inbred gliders have a host of health problems and it's just not responsible to allow or intentionally breed your rehomed gliders, period.
If you want a joey, go to a reputable breeder and buy a pair, that can remain a pair.
Or get your males neutered and buy another joey from a reputable breeder that you can introduce safely to your boys.
Or go do some research on breeding, and buy a legit breeding pair with lineage, I would caution you that I think you will be out of your depth if you choose to breed. Even with a healthy lineaged pair of breeders there can be issues that you are not prepared for. You will would quickly find yourself overwhelmed with joeys and you would need extra cages extra wheels extra everything. Any male offspring will need neutered even if you keep them to prevent inbreeding. It's a lot to take on, even experienced long term owners aren't always prepared for breeding.