BLE tags advertise packets at specified interval, BLE scanner scans for them also in intervals so called scan windows. Advertising frequency must be high enough so scanner can detect at least one valid packet before object leaves antenna range. If moving tag is moving fast enough chances of registering a valid packet are going down dramatically. To make it more reliable you would need to to increase advertising frequency (and there is a limit in BLE specification) and make antenna range wider (less directive) which will decrease precision. It may work, but technology imposes some limitations which may not satisfy your requirements. There are other technologies like RFID which may better suit your needs.
There is no dedicated connector on LTE Beacon to connect any external BLE antenna. You will need to solder it yourself and modify existing radio line (this might require some PCB trace cutting and matching line impedance).