Importing PowerShell module in ASP.Net

Is there anything special that I need to do to import a PowerShell module in C#?

I am trying to use the excellent PSTerminalServices module (https://psterminalservices.codeplex.com/) to perform TS tasks.

The following works perfectly in a PowerShell session (with elevated privileges):

PS> Import-Module PSTerminalServices

PS> Get-TSServers

However, if I attempt to use C#, I do not receive any errors when I try to import the module, but I receive the following error when running the cmdlet Get-TSServers: 

"The term 'Get-TSServers' is not recognized as the name of a cmdlet, function, script file, or operable program..."

which seems to indicate that the module was not imported successfully.

My code is as follows:

            var ps = PowerShell.Create();

            ps.Commands.AddCommand("Import-Module").AddArgument("PSTerminalServices");

            ps.Invoke();

            ps.Commands.AddCommand("Get-TSServers");

            Collection<PSObject> results = ps.Invoke();

I also tried using InitialSessionState, as described here: 

http://nivot.org/blog/post/2010/05/03/PowerShell20DeveloperEssentials1InitializingARunspaceWithAModule

... and received the same error.

Is there any way to check if the module imported successfully?

Thank you.