The quick answer is Yes, you can do it if there are No Other Options! But, IMO, the Best Answer is Don't!
The Pork Tenderloin, we are talking the small strip of meat about a pound or so in size, that usually comes 2 to a pack, is low in Fat and Connective Tissue. This makes it extremely tender and like a tender Beef Steak, is best Seared and/or Dry Heat Cooked, ie, stove top pan, oven, broiler, chargrill, to no more than an internal 135-140°F. Just like you would not ever consider putting a hunk of Beef Ribeye, NY Strip or Filet Mignon, in a Slow Cooker, Pork Tenderloin will be better cooked by ANY other means....JJ