Hi @black.beaker,
It looks like this is a result of running out of memory between your different threads, causing the odd failure you see:
https://github.com/benjjneb/dada2/issues/273
Since you set:
--p-n-threads 0
QIIME 2 will attempt to infer how many threads are available and use that, but it's possible we've got something wrong there.
How much memory and how many physical CPU cores do you have (also how many logical)? If you know the CPU model I can look that up as well.
In any case the solution is to reduce that number of threads you use, maybe try half the number of cores you have?
P.S. I would also recommend using the upgraded QIIME 2 which includes a more recent DADA2. You would still have gotten the same error likely, but at least it would have made more sense 