msrivas2- I don't think we can get deleted messages using rest API, the only way to get the details of deleted messages is using audit logs.
Documentation: https://community.lithium.com/t5/Community-Moderation/View-moderation-audit-log/ta-p/109763
Is there any option available to automate this process by creating endpoint or any custom component?
If yes then please share the the reference link.
You can use event subscription and subscribe MessageDelete event.
Here is the documentation https://community.lithium.com/t5/Developer-Knowledge-Base/Subscribing-to-community-events-using-the-REST-API/ta-p/14785
