I've tried every combination possible, it always boils down to the same thing. Either a phone works on the Dell switches or it doesn't, but it always works on Cisco.  I honestly think it is a power negotiation issue with the Dell switches, I'm just not sure how to prove/disprove it.   The phones are Lync phones and have no configuration that you can adjust.  I know nothing about the building access system, I didn't even know it was PoE until we made the cut over and it stopped working.