BMW usually doesn't change some things and in the past...the contact is made (to turn the mirror on) in the "support" that secures the mirror on the opposite end of the hinge (nearer the interior rearview mirror).
I haven't studied this area of the e70 to say this is for certain...but see #2 & #3 in pic below...check yours to see if this is where contact is made and if yes...then make sure nothing is preventing contact from happening. Again, there's more info at the link provided below...perhaps the electrical connection to the light is on the hinge side for the e70: