First let me say I am sorry you have to go through this journey. Prayers to your FIL.
Heres a few questions, is the diagnoses three seperate types of cancer or is it all from the kidney and has spread to the other areas. If he is in pain has he had a bone scan? Could be in the bone as well. I know thats not what you wanted to hear. However these are all common places for kidney cancer to spread.
Treatment theres choices, where 6 yrs ago there was only one option. SO thats a good thing. Has he had his kidney removed? As this is usually one of the first things they do. However it also depends on how large the tumor is and how far and bad it has spread. Please let us know more on what the docs have said so w can better respond. I hope this has helped some.
Prayers and thoughts to you all,
A Friend Lilsis