Is he able to "text" or simply get a message to them????
Texting is a specific method of contact. There are many ways to send a message without actually "texting" them. Snapchat, Twitter, Instagram, etc... are all examples of ways to send a message without having "texting" restrictions prevent someone from doing so.
If you also have "data" restrictions on the device but it is on wifi at the time, those "data" restrictions would not apply, either.