Very sorry to hear about your brother in law. That is a tough ordeal.
My son has brain cancer and was determined to be terminal last winter. He did not want to stop fighting so he was able to try an experimental drug thanks to President Trump who got the Right to Try legislation passed. On the first night of the RNC Natalie Harp talked about it.
So it was too dangerous for someone like my son to go to a clinic and be around other people. They set up a small office in a separate building for that purpose. He would go in and be the only patient there. They could do the blood draws and such and then clean the place thoroughly for the next high risk patient.
I am sorry to hear of the difficulties you and your family have been going through.
Saddly my poor brother-in-law spent over 40 years married to a person who made him miserable most of the time. I hate to say it, but when he got the cancer diagnosis I fear that he saw it as a way out. He did have a parade of people who came to say their goodbyes. He had no fight in him at all. No attempts of any kind were made to extend his time on this earth. He died much more quickly than predicted, more likely the result of over-medication than Covid.
In early 1990 he came to my wife and told her he had fallen in love with another woman. They were always very close. She told him he should fix his relationship with his wife, so he tried. She now feels that she should have told him to follow his own conscience and heart and not have interfered. He was a great guy and just retired a couple of years ago.