The physician is your candidate. Add them to your CRM/ATS — the physician has consented to this by engaging — tag them as Messly-sourced, and run your normal process: credentialing, submittal, placement. You don't need to go through Messly to communicate with them from here.
Tagging matters: when a Messly physician is placed, your agency's monthly report has to pick them up, so always mark the source.