[Python.NET] System.IO.FileNotFoundException: Unable to find assembly 'MbtCom.dll'.

Hi All, I know this is a very basic question, but despite all my efforts I haven't been able to load a third-party dll into python. I can find the dll using clr.FindAssembly("MbtCom"). I also append the required path to the sys.path, but it refuses to show up. Is there something obvious I am missing ? Thank you for your time.