I would have gathered a list of group members first using Get-ADGroupMember $ADGroup -Recursive
and then matched the users against that, ex:
$pattern = [regex]::Escape($OfficeOU)
Get-ADGroupMember $ADGroup -Recursive |
Get-ADUser -Properties * |
? { $_.Enabled -and $_.PasswordNeverExpires -eq $false -and $_.passwordexpired -eq $false -and $_.DistinguishedName -match $pattern }