Really not sure, lot's to pick from for one PPR flex spot... please help

I have Ajayi & McCaffrey @ RB (not super excited but is what it is)
Julio & Keenan Allen @ WR
Now I just need one Flex spot for a 0.5 PPR… Sitting at 3-3 and feel this week it crucial.
Please help guys

Marshawn Lynch (Thurs in which I would obviously move to RB spot)
Rob Kelly
Wendell Smallwood
Derrick Henry
DeVante Parker
Terrelle Pryor

I feel like I want to take a flyer on Henry because of his production last week & having the Browns. But all have disappointed at some point, if not completely, this season.

Thanks guys.

I would go with Henry as well. Parker probably will not play. Pryor is a train wreck this season. Lynch is very limited on touches, I am not a Kelly fan and I definitely do not like the match up against Philly’s run defense, and Smallwood is just returning from injury.