Have I correctly verified Core?
I've done this following but am a bit out of my depth:
4. Downloaded SHA256SUMS.ASC from Bitcoincore.org
5. Verified SHA256SUMS.ASC was created with Wladimir's certificate via Kleopatra (*See below)
As far as I can tell this is correct, but step 5 has me a bit unsure, mainly due to the following:

I am led to believe that this message is correct, and that 'The data could not be verified' is simply a result of me having not verified Wladimir's key via Kleopatra.
Does all of this look correct?
You must be Change Certification Trust from Wladimir's key to Full Trust or Ultimate Trust,