So doing some testing this morning.
(Test setup is Luma 8.2/B9/11.5/N3DSXL)
1\ RA.cia + Snes 2010 cia install and RA standalone runs (only after a game is run on SNES2010 cia). RA will then load with the SNES2010 core still loaded, and error with Storage Removed if any other core tries to be loaded.
2\ Uninstall SNES 2010.cia and RA black screens. No ARM11 fault is initialised, just a black screen. Couldn't find a log file in the retroarch directory however.