Migration process seems to work and computer account has been removed from source domain and created in target domain.
Domain membership of the computer has been modified but computer did not reboot.
One of the possible reasons for this behaviour could be the group policy which applies to the workstation and prevents the service account from rebooting the workstation.
Verify if the GPO is configured and if required grant the QMM service account the rights to reboot computers.
The policy "Force shutdown from a remote system" can be found under GPO\Computer Configuration\Windows Settings\Security Settings\Local Policies\User Rights Assignment.
Another reason for such behavior could be the local security policy of the desktop that is being migrated, it might have the "Force shutdown from a remote system" right enabled and has the Administrators group added.
"Force shutdown from a remote system" can be found under
Computer Configuration\Windows Settings\Security Settings\Local Policies\User Rights Assignment
Determines which users are allowed to shut down a computer from a remote location on the network.
This user right is defined in the Default Domain Controller Group Policy object (GPO) and in the local security policy of workstations and servers.
On workstations and servers: Administrators.
On domain controllers: Administrators, Server Operators.