How to make gil.

Can I do the mob nuking as RDM/SCH? Unfortunately I don't have BLM leveled very high. It's only 44.

I don't see why not, rdm would have less less trouble with enfeebles. As long as you got a decent nuking set you should be fine I did it all the time as rdm in sea farming organs.

RDM Nuking is much weaker than BLM, it takes longer, but its even easier in terms of real difficulty because Gravity is that much easier to land.