I had downloaded it and waited for the done message, but I can't recall what the output was at the time. I've done the reinstall as you suggested though and got the following steps performed.
Uninstalled plugin, rebooted server.
Reinstalled plugin. Output was: -
plugin: installing: https://github.com/ich777/unraid-hpsahba/raw/master/hpsahba.plg
plugin: downloading https://github.com/ich777/unraid-hpsahba/raw/master/hpsahba.plg
plugin: downloading: https://github.com/ich777/unraid-hpsahba/raw/master/hpsahba.plg ... done
+==============================================================================
| WARNING - WARNING - WARNING - WARNING - WARNING - WARNING - WARNING - WARNING
|
| Don't close this window with the red 'X' in the top right corner until the 'DONE' button is displayed!
|
| WARNING - WARNING - WARNING - WARNING - WARNING - WARNING - WARNING - WARNING
+==============================================================================
-----------------Downloading hpsahba Patch, please wait...!--------------------
-----------This could take some time, please don't close this window!----------
-------------Sucessfully downloaded hpsahba Patch, please wait...!--------------
----------------------hpsahba Patch already installed...!----------------------
plugin: hpsahba.plg installed
Updating Support Links
hpsahba --> https://forums.unraid.net/topic/92865-support-ich777-nvidiadvb-kernel-helperbuilder-docker/
Finished Installing. If the DONE button did not appear, then you will need to click the red X in the top right corner
Clicked on done, opened the console and entered hpsahba -v and got bash: hpsahba: command not found.
I'm not sure, is that line hpsahba patch already installed confirming the kernel patches are in, which they should be as I used the kernel helper to get them in, or is it thinking the command is already installed?