It seems as though enabling the DTLS handler component no longer functions on Xbox, and it's possible enabling this packet handler no longer works on other platforms as well.
It may also be worth investigating adding DTLS support to Lyra.
Enable the DTLS encryption packet handler component in a project on Xbox.
When the SSL module is started up in FDTLSHandlerComponentModule::StartupModule, it won't create a SSL manager because WITH_SSL is still 0, leading to the check in FSslModule::GetSslManager being hit.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-171638 in the post.