TCU Recall on 2004 X5

[GAnGA]

Forgive me if I've repeated a question already answered elsewhere, but my searches have come up fruitless.

I today dropped my 2004 X5 (8/04 prod) at dealer for TCU recall (letter from NA advising that Assist module was malfunctioning). From previous posts since 2004, I understood that by replacing the 2004 Assist TCU with one from 2005+, I would gain the ability to use Bluetooth, which was lacking before.

As it is now 2007 and the dealer advised that the "latest model" TCU was installed, I believed I should now have functioning Bluetooth along with Assist.

Dealer advised midday that new TCU was installed, but they were having trouble pairing a phone with the Bluetooth.

Several hours later, Dealer called back and reported that "this" TCU did not, in fact, support Bluetooth--but I could buy one that would for about $1100.

I get the sense that something doesn't seem right with this assessment; but I'm not sure how to rebut when I pickup my truck tomorrow.

Am I correct in my belief that Bluetooth should now work in my X5? Or is my system still missing a component necessary for BT to work? Or is dealer being straight with me--the replacement TCU is different than others that are the BT/Assist combo used from MY 2005 on?

I appreciate any advice!