To answer the questions about LoRa.
In tests I have done then based on similar data rates and powers, LoRa does have a slight advantage (5dB or so) over FSK RTTY, even when you comapare a £5 LoRa device to a good quality (expensive) amateur radio reciever.
The LoRa setup can also be left to run unattended, it does not need the re-tuning required when using FSK RTTY at the receiving end.
You can indeed use LoRa with dl-fldigi, you just need to arrange for the LoRa receiver to re-transmit the received tracker payload as AFSK RTTY audio via a PC soundcard.
Lots of stuff on LoRa here;
For the simplest of LoRa based HAB trackers read this, it does LoRa and FSK RTTY;