Email to Text Message Notification

I'm trying to set up a text message notification for an "emergency" email account as my company is closed between Christmas and New Year's Day and I'm running into an issue with sending messages to Sprint customers, which is really weird.

I can successfully send the stock message that I have to customers @txt.att.net and @vtext.com for AT&T and Verizon customers, but when I try to send a message to @messaging.sprintpcs.com my message status says that everything went successfully, but the text is never received. Now to pile on the weird... I can create a plain new email message and copy and paste the Sprint text message address from the same rule that I'm trying to create and the message successfully goes to the phone. So to recap, email to text by a rule doesn't work, but email to text by a stand-alone message goes through without a problem. Everything seems to be tied to the email to text being generated automatically and on the Sprint network only. Sprint is pointing me to something with how the message is getting sent from GroupWise because a manual message will successfully go through but not the automatic ones. Has anyone ever heard of something like this?