I have a 2011 SRX AWD it can be flat towed but the manual on the 2011 is wrong when I read it I saw a problem & contacted GM .
They said a revision was made to the manual & I got the revision from the Caddy dealer. I believe the manuals after 2012 are correct-- don't know what year yours is. Maybe this will help:
Revised Dinghy Towing Procedure #PI0268B (June 30 2011) Models 2010-2012 Cadillac SRX
Hope it helps you.