Hi J,I don't think the level shifting is needed, because the MISO drops to ~ 2V, when connected to PIC.
Have you checked your program, if the other devices ( BMP280, LCD ) are off.
Could make a test program only for the compass and possibly disconnect the other devices from MISO.
You said in #1 that the radio is one of the SPI devices??
[ I don't think the level shifting is needed, because the MISO drops to ~ 2V, when connected to PIC. ]
The images #117, show lower than ~2V, when connected to PIC.
[
Have you checked your program, if the other devices ( BMP280, LCD ) are off.
Could make a test program only for the compass and possibly disconnect the other devices from MISO. ]
Did you see the EDIT at #117? No difference with Radio disconnected.
C