I see what you mean about >20,000A with a dead short circuit.
Taking one of the test report values for my Eve LF280K cells I get;
Code:
3.296V / 0.00014Ω = ~23500A
However, that's only if there's a short directly between the terminals of the battery...
Wire resistance ends up being pretty significant though I think. For example every two feet of 2/0 cable provides another 0.00015Ω of resistance so if there were just two feet of 2/0 cable involved in the short circuit that amperage would be approximately halved.
I'd need to measure some cable lengths and do a bit more math, but I wouldn't be surprised if I'd be in the right ballpark for the ANL fuse I've got and maybe even safe with just the Blue Sea breaker.