No it doesn't make a difference. Idk why it wouldn't Mount your flash drive. FYI if you reformat data as ext4 you don't necessarily have to reflash the ROM. It should still let you get in so you can restore your sdcard data from you otg drive. Then after that I would reflash.
I think that the ROM itself is not supporting f2fs... That's the only thing I can think of. If you want you can try cm11 but I don't think that will with either. I'm gonna see if maybe I can make a flashable zip with f2fs tools.
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