Your system seems to be a Compaq 6000 Pro. If this is correct, there's a BIOS update released in 2015 to which you should update and retry ventoy.
I studied the changelog/revision history (this version and previous versions) and found a lot of issues fixed regards to booting.
https://support.hp.com/in-en/drivers/sel...c-156845-2
I studied the changelog/revision history (this version and previous versions) and found a lot of issues fixed regards to booting.
https://support.hp.com/in-en/drivers/sel...c-156845-2