F5 BigIP v.15 integration with Windows 2016 NPS
I was able to get this to finally work using a combination of articles here :
You want your Windows NPS server to return the attribute value of 0 (0=admin or whatever # using the F5 VSA article) to F5 BIGIP to let that user in.
Here are some screen shots of the network policy.
You want to define the vendor code to 3375 (F5)
You want to set the vendor-assigned attribute number to 1 which the F5 line for the user role (that can be found in that f5 article) :
ATTRIBUTE F5-LTM-User-Role 1 integer
You want that vendor-assigned attribute number of 1 to pass the DECIMAL value of 0 which is the admin level to the load balancer.