My mom is in end stage of parkinsons and on hospice. She’s now stiff and arm is swelling, does this mean death is soon?

Stiffness alone is very common with Parkinson's. I don't know about swelling of limbs.

Probably time to consult the Dr. Hopefully you can do a virtual visit.

Mom is on hospice? Then you can ask the hospice care team. At some point, hospice does help facilitate a painless (we hope) passing. What happens before that is as unique as the person themselves.

Take Care.

LM, overall assessment is just impossible from this Forum, even for someone who spent a lifetime as a nurse. You should talk with your hospice personnel. They may be hesitant to guess. Often the best assessments, the best "guesses" are wrong. Each human body is as unique as a thumbprint.
I hope you are drawing comfort from Hospice, and that your Mom is comfortable? Our thoughts go out to you. So glad you are there with your Mom. I hope you will keep us updated.