yes it does. There is no way to know if they will be to closely related unless they have lineage.
Some folks think that just because they got gliders from 2 different people in 2 different states it should be ok and they probably aren't related.
But that isn't so, It doesn't matter where the gliders come from they could still be to closely related. Gliders have been shipped to legal states for years you can buy a glider from Ny and a glider from Florida and they could be closely related.
If you bought the girls as pet only but had the option to buy lineage you can sometimes talk to the breeder and purchase the breeding rights which means they will provide that gliders lineage.
Out of my current 9 gliders I have one female and her 2 daughters with lineage I can breed if I choose to. The rest are rescues/surrenders, personally I feel it would be irresponsible ( as does the majority of the glider community) to breed rescue/surrender gliders. None of them have lineage, and some I have very limited information of their history. They are and always will be pet only gliders.
If I were to breed more I would invest in a lineaged male, all my males are currently neutered. To do that I would speak to a few different well known breeders and ask for assistance with a good pairing for my female.
Lineage and Kinship are not my strong suite and I just don't know enough about it to feel comfortable choosing a safe, compatible male. I did not pair up my original breeding pair my mentor did it for me she taught me the basics and IF I had to I could probably figure it out, but I'd be more comfortable to let someone more experienced and knowledgeable with all that do it even though I have no intentions of selling joeys, they would all stay here.
In that breeding 101 group there are tons of people that are happy to compare lineages for new breeders to help with safe pairings. If you are really interested in learning how to do it yourself they will teach you that as well. In fact there are learning scenarios in the posts where they provide 2 gliders lineage and people have to figure out the kinship and percentage of the pairing.
Now having said all that.
Is lineage completely 100% accurate and 100% reliable? NOPE!
there are some made up lineages, their are some mistakes, there are things that don't add up.
BUT, it's all we have, to do the best we can to breed ethically and responsibly.
Lineage, for the most part, is kept track of on the pet gliders site. https://www.thepetglider.com/pages/pedigree-program
Which goes back to the "founding gliders" the first gliders entered in this database. Like I said it's not a perfect database, but it is safer than breeding gliders with no lineage at all.
I hope this helps to answer your question and hopefully it made you have more questions