At 200m I’d expect a far higher (or lower, as you brain works) RSSI. Somewhere around -90 which is sort of a guess value, but -114 is definitely in the km range so this isn’t ideal.
[Note to self, take Mappy for a walk]
As I suggested, the antenna on your device, which is relatively ancient technology, isn’t the greatest considering how close it is to a gateway. You need to optimise the signal path - line of sight, no big obstacles in the path.
Unless you are auditing the heck out of the messages for some legal submission or trying to catch Hannibal Lector, you can ignore the correlation ids. They do join up the whole sequence but are like drinking from the Matrix fire hydrant.
Can you tell us when you compile the sketch how much memory & flash is used / available. The memory available is essential to how well LMIC can process downlinks - too little and errors / drops will occur.
For LMIC, I’d go to an Adafruit Feather M0 with RFM95 - more program space, well built, minor hardware mod required for LW.
Or go for an ESP32 or Feather M0 using RadioLib which is more compliant / up to date.