Then your doing something wrong, or one of the SPI devices on the bus is not able to correctly share the SPI bus with other devices..........
This is how I would setup a LoRa device and an SD card on same spi bus;
SPI.begin();
LoRa.begin(NSS, NRESET, DIO0, LORA_DEVICE);
SD.begin(SDCS);
And it works, no select pins passed to the SPI library .......
Start with the basic LoRa sender sketch, make sure it works, then start adding stuff to see when it fails.
There could be a hardware issue here, so searching through a long pile of code for an 'error' may not identify the problem. If a device does not share the SPI bus properly then you wont be able to tell that from looking at the code.