Gardenia question

[Angelo585]

I have a customer that is dead set on using G. Jasminoides "frostproof" aka Frost Proof Gardenia, I have previously used it successfully in zone 7 but this customer is in zone 6b (Rochester, NY). I have advised that it was not a good idea due to it not being hardy. The customer then printed out a page from a grower or nursery website saying it is hardy to USDA zone 6. I went and did some research on this and found conflicting info, in fact Monrovia's site says zone 6 on one page and zone 7 on another.

Does anyone know the real story on what zone this plant is hardy to, also the customer wants to use it on a south facing wall as a foundation plant.
Could this plant be wintered over in zone 6 by using a protective burlap tent or cover over/around it?

Thanks in advance for any feedback guys....