Thanks BuzzPCSOS, I am using a 64GB Ventoy stick, but have tried ImgBurn prepared sticks as well with no luck.
The big issue is that I can start up using F9 through F12 and will unfailingly get the HP splash screen, but cannot proceed any further beyond that, so trying to dig around in the BIOS is exactly what I am trying to do.
I have also tried the DVD option with Solus ISO, but to select the optical drive have to go through the same steps as mentioned above... which does not work.
The only option left is as you suggest is removing the hard drive completely etc., but you are right about my MISGIVINGS about that. Anyhow I ill have to do something, so I'll have a good look at that video again and hope to gather enough guts to enter the wilderness of the laptop innards...
One question though: will removing the hard drive serve any purpose in this case since there is supposedly nothing on there (wiped completely by the Solus installer)?