in administration -> audit -> actions, "recipient" column contains information from "send to field". unfortunately, user account name is not shown (except in some error messages, like "No media defined for user "monitoring user (monitoring_user)"").
it's not always obvious which user has a specific email address, especially in larger installations where multiple system integration accounts might exist. would be great if a separate column was used to store user account name in "alerts" table, and displayed in this list.
while that table already has userid column, it's not long-term safe solution, because user might get deleted, and in that case information would be lost.
for added bonuspoints audit view could check whether username from the alert matches current username with same 'userid'. if it's different, it would show "(now named NEWNAME)", if it's missing, "(user deleted)".