I wish I could blow the picture up on this computer.
But, it looks to me like a poorly done neuter at a young age. Sometimes, when they are neutered by methods that we would not condone on this forum, and when they are neutered very young (which those who do not use a vet for neuters will often do), then we are left with issues later on. This is particularly true if the glider happened to be a chryptorchid (meaning one or both testicles did not descend).
chryptorchid gliders will be sterile, but will also still have hormones. My Aramis still has one testicle somewhere up in his abdomen. He is sterile, but has an obvious bald spot and a mild smell when his cage mate goes into heat. He is also still amarous.
Since this one is young, it is not surprising that the chest scent gland is not noticable. It often is not in gliders neutered young.
That's my 2 cents.
I also know that there has been at least on person on the boards have a girl with a very, very small pouch. So, I guess that is a possibility.
I would take the glider to a vet. Or, at the very least, to someone in the area with a lot of experience. If the "next state" is VA , then maybe she is near Aimee (whom I think is in Arlington???) Or maybe she is near another community member with enough experience to feel that baby up and see what she has. LOL.