I would expect EAI_FAIL or EAI_AGAIN, but I'm pretty sure we're getting EAI_NONAME.
But, the stuff that hits this problem the most often is of the quality level that I wouldn't find that terribly surprising. Seems AWS "documents" this as,
> The number of DNS queries per second supported by the Amazon-provided DNS server varies by the type of query, the size of response, and the protocol in use.
How specific.