We are having issues attempting to create a linked mailbox within ADManager.  After the creation of the AD account (within ADM) we run a custom script at the end of it.  Command in ADM template:

C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -version 2.0 -noexit -ExecutionPolicy ByPass "C:\Scripts\NewLinkedmail.ps1" -Arg1 %sAMAccountName% -Arg2 %givenName% -Arg3 %sn% -Arg4 %mail% -Arg5 %displayName%

The powershell script referenced contains:

New-Mailbox -alias %samaccountname% -name %%givenName% %sn%% -database "DB2" -org "mydomain.org/OtherAD/Migrated" -LinkedMasterAccount %mail% -LinkedDomainController dc4.OtherAD.com -UserPrincipalName %mail%

It always fails though.

If we instead run the following powershell script manually it creates the linked mailbox correctly:

New-Mailbox -alias tsmith -name "Tanner Smith" -DisplayName "Smith, Tanner" -FirstName "Tanner" -LastName "Smith" -database "DB2" -org "mydomain.org/OtherAD/Migrated" -LinkedMasterAccount tsmith@otherad.com -LinkedDomainController dc4.OtherAD.com -UserPrincipalName tsmith@otherad.com

Any ideas?

Exchange 2016 CU5.