Was just reading the error message and it sounds like the installer thinks that you are trying to install the wrong CU.
I would try re-downloading CU 22 and see if it might be a bad download or a bad link for the update?
The error is saying that your version is newer than what the CU is expecting.
Alternately, you could try installing CU 21 first. You shouldn't need to, but it may be a bug in the CU 22 installer that it doesn't like installing on top of CU 20?