Please check the video at:
https://www.youtube.com/watch?v=YTuZ-VHmqRo
There is no need to “pair” anything. Once the tags are in the advertising mode:
https://help.mikrotik.com/docs/display/UM/TG-BT5-IN#heading-Tagmodes
tags will broadcast information about themselves in the Bluetooth packet’s payload. This payload will be “broadcasted” over specific Bluetooth channels:
https://help.mikrotik.com/docs/display/ROS/Bluetooth
the KNOT will “listen” to the payloads on those channels and display them under its Bluetooth interface. There is no “pairing” involved. Tags broadcast packets and KNOT just captures/displays them.