Check AD property 'msRTCSIP-BaseSimpleUrl' of abcd@example.com on each domain controller.

One of the way how it can be done is by performing Lync cmdlet:

(Get-CsOnlineUser abcd@example.com -DomainController <DC>).BaseSimpleUrl

ex:
PS C:\Users> (Get-CsOnlineUser abcd@example.com -DomainController IHM-CAM-DC-1.example.com).BaseSimpleUrl
https://meet.lync.xyz.net/example.com/Meet