There are two different packages that BMW sells, an extended warranty and an extended maintenance plan. They are exactly what they describe but two distinct products.
If the car truly has a BMW extended warranty, the only way it does not covert the car is if the mileage is that high. I forget exactly what the extended warranty covers but want to say it should be the same, good until 04/2016 and 100k miles.
Again, BMW dealers usually offer both BMW warranties and third-party warranties. The only way I can see your car not being covered is if the warranty was actually a third-party warranty that was not properly transferred when the original owner sold/traded it in...
Might want to call BMWNA to see if they can use your VIN to check for the BMW warranty because your service rep either doesn't know what he's talking about or he's simply not giving you all the information. It should be pretty straight forward for him to find out if it is a BMW extended warranty (which would still be in effect) or a third-party warranty...
2011 Space Grey E90 M3, DCT, Comp. Pkg.
1997 Z3 2.8, Artic Silver, Tanin Red interior, MT
1974 2002tii, Inka, MT