Flex for Week 3

I got:
Chubb, Devonta Freeman, Montgomery
Adams, DJ Moore, DeMarcus Robinson

Need 2 RB, 2 WR and another flex.
So far, leaning towards starting either Montgomery on flex, but debating if Robinson is the better choice considering last week’s performance.

Or… would you start both Robinson & Montgomery and sit DJ Moore this week given Cam’s injury?