Shotgrid Summary notes going to email

When using the Review Notes app and sending an email summary, some users a my company have reported that they have not received the summary email when sent to their email directly. We have tried a few tests:

  • Sent the review notes to users with the “CC Email” field to a group email alias, and the email appears in their inbox
  • Sent the review notes to users with the “CC Email” field to an individual’s email alias, and the email does not appear in their inbox

Has anyone experienced a similar issue? Our company uses Gmail, and these users have the same Shotgrid email notifications as myself (and I am receiving all the emails)