FIXED - worked for 2 different Servers. intel i7-6950X and amd 5950x
Edit the VM XML (XML VIEW)
STEP 1.
add
<kvm>
<hidden state='on'/>
</kvm>
before </features>
Step 2.
add
<feature policy='disable' name='hypervisor'/>
before </cpu>
*do not delete or replace, only add*
Example
<features>
<acpi/>
<apic/>
<hyperv>
<relaxed state='on'/>
<vapic state='on'/>
<spinlocks state='on' retries='8191'/>
<vendor_id state='on' value='none'/>
</hyperv>
<kvm>
<hidden state='on'/>
</kvm>
</features>
<cpu mode='host-passthrough' check='none' migratable='on'>
<topology sockets='1' dies='1' cores='8' threads='2'/>
<cache mode='passthrough'/>
<feature policy='disable' name='hypervisor'/>
</cpu>