Bols has an interesting article on suffer vs loses, but they couldn't work it out either. They seem to suggest it either:
negates the wound before damage being applied (suffers) and as such potential negating all damage vs loses being a roll for each wound lost.
or
it works exactly the same way rolf.
Did GW ever clarify if they actually intended on making a difference?
Either way its more about if "Wound" means any wound or if mortal wounds is treated as a separate thing.
Turns out, its in the rule book FAQ, page 4 and "wounds" in this sense, is no matter the cause. Which makes the craftworld codex wording redundant.