Has anybody used the BCA-Z Bluetooth adapter on the DT800 series telephones?

I have a customer that has a hard of hearing staff member and looking for solutions. She has a Bluetooth headset that she uses at home as well as on her smartphone and wondering if we can make it work at the office too. Using the BCA-Z, will it allow her to integrate directly with the phone to answer calls or will we need other hardware? Could not find anything more than a basic installation manual on the NEC website.

She has a Sennheiser headset, similar to a Plantronics M22, on their current Panasonic system but it does not work well.

Any information would be greatly appreciated.