I found a solution and changed only this command:

$createdGroup = Invoke-PatchGroupForDomain -Server $n -DomainId default -Group $group -GroupId $GroupName

to

$createdGroup = Invoke-GlobalInfraPatchGroupForDomain -Server $n -DomainId default -Group $group -GroupId $GroupName

With Get-Command -Module VMware.Sdk.Nsx.Policy we get all the necessary commands for NSX Module.