I’m sorry I cannot be of further assistance. Maybe contact Multitech directly.
Here’s some more references for xdot from Multitech: MultiTech Developer Resources » Downloads
Here’s a reference to the bootloader too: GitHub - MultiTechSystems/bootloaders: Bootloaders for mDot, xDot, MTQ(Dragonfly) and MTQN(Dragonfly Nano)
AND>>> here is MultiTechSystems DAPLink github page: GitHub - MultiTechSystems/DAPLink