I'm not getting that impression from the status update:

"We can confirm that resolution of .io domain names are intermittently failing due to issues with the .io TLD name servers that are hosted external to AWS. Route 53 name servers continue to operate normally, but customers who have sub-domains of .io hosted on Route 53 may experience issues until the .io TLD name servers hosted externally are resolved."

how can that be related to Route53? Nameservers are managed by .io TLD and that's where the issue is coming from. If you use Route53, the nameserver should return Route53 nameservers