'migrate' says it worked but in reality it did not - centOS 9

[lejeczek]

Hi guys.

I have a peculiar situation where between boxes:
C->A
-> $ virsh migrate --unsafe --live c8kubermaster1 
qemu+ssh://10.1.1.99/system
-> $ echo $?
0
but above does _not_ happen, instead!! VM was stopped in 
started, but _not_ migrated LIVE

A->C
-> $ virsh migrate --unsafe --live c8kubermaster1 
qemu+ssh://10.1.1.100/system
-> $ echo $?
0
indeed VM migrates live.

box A & C have virtually identical OS stack,
HW difference is:
C = Ryzen 5 5600G
A = Ryzen 5 3600

domain XML snippet where I think it matters:
...
   </metadata>
   <memory unit='GiB'>4</memory>
   <currentMemory unit='GiB'>4</currentMemory>
   <vcpu placement='static'>2</vcpu>
   <resource>
     <partition>/machine</partition>
   </resource>
   <os>
     <type arch='x86_64' 
machine='pc-i440fx-rhel7.6.0'>hvm</type>
     <boot dev='hd'/>
   </os>
   <features>
     <acpi/>
     <apic/>
   </features>
   <cpu mode='custom' match='exact' check='full'>
     <model fallback='forbid'>EPYC-IBPB</model>
     <feature policy='require' name='ibpb'/>
     <feature policy='require' name='ssbd'/>
     <feature policy='require' name='virt-ssbd'/>
     <feature policy='disable' name='monitor'/>
     <feature policy='require' name='x2apic'/>
     <feature policy='require' name='hypervisor'/>
     <feature policy='disable' name='svm'/>
     <feature policy='require' name='topoext'/>
   </cpu>
   <clock offset='utc'>
     <timer name='rtc' tickpolicy='catchup'/>
     <timer name='pit' tickpolicy='delay'/>
     <timer name='hpet' present='no'/>
   </clock>
   <on_poweroff>destroy</on_poweroff>
   <on_reboot>restart</on_reboot>
   <on_crash>destroy</on_crash>
   <pm>
     <suspend-to-mem enabled='no'/>
     <suspend-to-disk enabled='no'/>
   </pm>
   <devices>
     <emulator>/usr/libexec/qemu-kvm</emulator>
     <disk type='file' device='disk'>
...

Initially I submitted a BZ against 'PCS' but continued to 
filled with it and I find 'libvirt' might be the 
culprit(also?) here.
There is not much in logs, certainly nothing (with default 
verbosity) in virtqemud.service
Is it that VM gets migrated but then is restarted on 
'migrate_to' host? if so then why?
How to start troubleshooting such 'monstrosity'? - all 
suggestions appreciated.
many thanks, L.