Trying to print a tabloid booklet but it's only printing on 8 x 11.

Hi there,

I am trying to print a booklet to my office printer but it seems that no matter the settings I turn on or what I do different, it always prints on 8x 11 or letter sized paper. 

My coworker (can print booklets on tabloid) sent me his settings to see if I can match them, and even though I have, everything I order to the printer comes out on the standard letter sizing. I even set the default printer paper size to tabloid but to no avail.  

If it helps, I'm on a Mac. I don't know if that changes things. I've attached screenshots of my settings.