You're not whining. You have been through so much and you have so much going on that you can't tell what is causing what. I have stage 2 lymphedema as the result of having 26 lymphnodes removed during a mastectomy. (Only three were cancerous.) I wear compression & a gauntlet and use a pneumatic pump to keep my arm and hand looking normal. My arm has rarely seen the light of day since 2020 and it looks like it belongs to the Pillsbury Doughboy. I was on Anastrozole, had a bad time on it and am now on Tamoxifen. That's another story. I'm afraid I'm not going to be all that helpful but I'll tell you what I know about lymphedema.
Some time after I developed it I developed rotator cuff syndrome, tennis elbow and DeQuervain's Tendonitis.
I knew this wasn't coincidence. I was sent to an OT who had experience with lymphedema. She told me that when you have lymphedema, every move you make with that arm takes more energy than normal because you have that additional fluid in your arm. I don't know this of course, but that might be why you have the hand pain. When I had the DeQuervain's I was sent to a OT who was trained in hand therapy. I learned some very gentle exercises.
Did the Depuytren's start since you have had lymphedema? I was told that many people who have lymphedema develop DeQuervain's and rotator cuff syndrome. Do you have a lymphedema therapist? It would be a good idea to check in with a PT who is LANA (Lymphology Association of North America) certified. She/he would know if the Depuytren's is related or being made worse by the lymphedema and if the hand pain is related to the lymphedema.
I always blame everything on being on the computer and sometimes it has nothing to do with it!

I did a quick Google search of side effects of Anastrozole and it did list swelling of the feet. You should let your oncologist know about this.

I am afraid this won't be too helpful. I just wanted you to know you're not whining. This cancer business is overwhelming sometimes. This is the place to ask questions and express your concerns.