No, they can't.
1) there is no network connection between the two world
2) the test env must run for a long time (many days), with a weekly refresh
In fact, the "restore to..." option is misleading here. You have a UI with "restore to original.tld" and "restore to...", that kind of presentation would suggest you can restore to something else than "original.tld".
I also remember having read a weekly digest from Anton (or a post from Lucas, I do not remember) of a Customer using VEAD to migrate his users between two domains. Has it been allowed in the past ?during the beta phase for example.
Veeamizing your IT since 2009/ Vanguard 2015,2016,2017