Need a flex play this morning!

Asked this earlier, just hoping for some more input. Who should I start in my flex, kerryon Johnson, buck Allen, or Geronimo Allison in my 12 team standard league? My current team is:
Brees
Elliott
Howard
Callaway
Tate
J cook
(Currently) buck Allen
Packers Defense
Dan bailey

I think I would go with J Allen.