Fair offer for David Johnson?

The team who has David Johnson is otherwise weak on RBs, he has: DJ, Crowell, Forte, and Lacy.
I have Freeman, Hyde, Martin, Cohen, and Charles - any chance something like Hyde or Martin + Cohen is fair for DJ?

I feel I may want to wait until there is a better sense of when vs. if DJ will return this season, but wanting to also gauge whether I have a fair offer to make.

Don’t need to give up too much for DJ. He might stay on your bench up until playoffs. And the DJ owner looks like any rb would help him.

So what is “too much” here? Offering Cohen alone doesn’t seem appropriate, and would need to pair him with more than Charles.

Maybe Martin and cohen? You should ask who he would want to gauge how much he values his players and yours.