First things first: Please create a minimal working example first.
In this case, create a new, empty mailbox, and then try to connect with your code to it. If that works, add a first mail, and try to retrieve it. Do it step by step, so you can verify your previous step is working.

In your openssl response, you get a response from MS Exchange Server, so both inbound and outbound networking is configured correctly.

You say it completes "successfully outside of AWS". How long does it take to complete? Is it close to the timeouts you've set? Could it be that your EC2 instance has less resources available then your "outside of AWS" machine and takes longer?

Try to increase the timeouts to let's say a minute. Does the behavior change?