2 Signature Document - activity log shows it was only sent to one person

I created a document that needs 2 other people to sign. The activity log shows the document was sent to the first person, who signed the document. It also shows it has NOT sent to the second person. I can set a daily reminder for person #2 but can't send them an immediate reminder to push the email through (they don't show as an option to check for immediate reminder, only I and the first signer do). I've triple checked the email and info for person #2 and it is all correct, and they have checked spam folders and have not received and email (which is not surprising as the activity log shows no email was sent to them). How do I push this to them so that they can sign?

Thanks!