Hi there, this is Dr Linda, a UK based vet.
I'm sorry to hear this and understand your concern for Babs.
Her signs are alarming, especially as she is an older hamster.
They tend to hide away when unwell and getting hold can be due to poor circulation, shock or organ failure.
We would not expect hibernation in the summer (unless you artificially made the room very cold).
Also, hibernation is not associated with the other symptoms you have mentioned, which confirm she is sick.
The fact she is barely able to walk, again, could be due to the conditions listed above or e.g. a recent trauma or brain tumour.
Hamsters should never have a soiled bottom and this could be due to an infection.
I'm concerned she may be close to passing away.
I'd urge you to seek veterinary assistance. She may well benefit from some antibiotics, anti inflammatories and assisted feeding.
The vet might be able to provide a diagnosis after checking her over.