Search and replace through SSH
SSH into the WordPress server and run the following command:
wp search-replace "mphdev01.wpengine.com" "testing.metroplus.org" --precise --all-tables --report-changed-only --dry-run
That performs a dry run, which does not change anything. Once you are ready to actually perform run:
wp search-replace "mphdev01.wpengine.com" "testing.metroplus.org" --precise --all-tables --report-changed-only
The code above assumes mphdev01.wpengine.com as the old domain and testing.metroplus.org as the new domain. You can change these to whatever you need.