I have a BT800, and I know Laird supplies a MAC address (0016A4XXXXXX), but the host returns a different MAC starting with (00 24 5B XXXXXX)?

Check your schematic and the HIG. It is probably "VDD_PADS" not being powered properly. It is the power rail of alI I/O pads including the EEprom. The MAC address is stored in the EEprom.