Replacement Warrenty Parts Problem

[NCBound]

Well to make a long story short and sweet, we have an 06' H2 with the rear entertainment system from the factory. The drivers head rest will not lock into the various viewing positions for the rear passenger (kids). Took the H2 in now almost a month ago and was told that they would replace the headrest under warrenty (the internal ratchet that locks it in place is totally busted). I have been working with Hall Hummer to get the parts in and even have called Hummer/Caddy 24 hour customer service and have a service ticket opened with them as well. They tell me that the headrest has to come from the supplier that made them for the 06' H2 headrest with the LCD screen built in. I just can't figure out what the big hang up is on these parts.... You can still purchase an H2 with factory rear entertainment package that seems to look the same as the 06' package. Hall tried to take the headrest out of an 07' to make the repair and they determined that they were not compatable????? Anyway I am just venting a little and was wondering if anyone else had this kind of issue. Any advice would be great and I am still waiting on the parts for going on a month now. Thanks in advance.