There are two separate questions to be answered here, Lynda.
Firstly, does he have prostate cancer? Three quarters of men his age do, so it wouldn't be at all surprising if he has. The tests will show whether or not he does. Don't be overly concerned about it. In many men his age no treatment is required.
Secondly, is the pain caused by metastatic cancer? With a PSA of only 10.6, this is unlikely. Not impossible - there are rare types of prostate cancer which don't significantly raise PSA - but for the common or garden type of cancer, adenocarcinoma, you'd expect much, much higher PSA levels to be associated with metastatic cancer. Please don't assume the worst - wait and see what the tests show. He's in the right place to get diagnosed quickly.
Best wishes,
Chris