Redis host name resolution failure

I have an app that uses Horizon where I process 30k jobs per hour on average. Horizon is running on multiple job processing servers, with a shared ElastiCache Redis cache implementation. Over the last two days, for an unknown reason, and oddly around the same time of day (0:00-2:00 UTC, which does not correlate with the maintenance window), the CPU has spiked to 60-100% on some of the servers. After a lot of digging, I found that the reason is due to intermittent Redis host resolution issues when processing jobs via horizon. An example error looks like this:

[2021-12-03 01:50:37][a88fcc17-70dd-4931-a119-87335e42f543] Processing: {JobName}
In UdpSocket.php line 65: socket_sendto(): Host lookup failed [-10002]: Host name lookup failure  
In UdpSocket.php line 65: socket_sendto(): Host lookup failed [-10002]: Host name lookup failure
In PhpRedisConnector.php line 141: php_network_getaddresses: getaddrinfo failed: Temporary failure in name resolution
In PhpRedisConnector.php line 141: Redis::connect(): php_network_getaddresses: getaddrinfo failed: Temporary failure in name resolution

I'm no Redis expert, but all Redis node (1 primary, 1 replica, cache.t3.medium) resources look like they're within appropriate ranges. CPU, Engine CPU, and DB Memory Usage percentages are all within 1-3%, and Freeable Memory is near 3GB. Because this error is intermittent, I don't believe that its a configuration issue, and it likely has more to do with resource utilization/threshholds or something along those lines.

Any thoughts or ideas? I'm totally stumped. Thanks in advance for any help or pointers in the right direction!