RNJack,
Alright, I think this is making a little more sense now.
So, your Mitel Vendor has lead you in the wrong direction as you most likely have figured out.
As for the putting a Softphone on a Smart Phone you would need two separate licenses for that.
1. Mobile License: This puts the Phone Manager client on your Smartphone.
2. Softphone License: This enables the Softphone option on a Phone Manager client [Mobile or Desktop].
Now, you would also need other licensing for each person, as you probably already know, but they do come in bundles as well as a-la-carte so don't worry.
I am kind of confused as to why your Mitel Vendor isn't doing this work for you since they are the ones trained for this and have support from Mitel, but I guess they are doing so well they don't need your money.
Anyway, lowradiation has already provided you with the guide, but if you need more help don't hesitate to ask.
Thanks,
TE