In the same boat as you Op. On the one hand you have Ryan who has only gone over 300yds 3x this year (@Chi, @Car, vs TB) and hasn't thrown for more than 2 TDs in a game.
However, his last 3 matchups at home vs. the Saints:
On the other hand you have Carr who as you stated hasn't cleared 225yds or thrown for more than 1 TD at KC. He will likely be without Cooper. But, he did throw for 417yds and 3TDs earlier this year against them at Oak and Peters is out as mentioned. He still threw for 287yds and a TD last week w/o Crabtree and Cooper but it was at home (vs NYG). Carr has thrown for over 300yds 3x this year (@Buf, @Mia, vs KC) and thrown for 3 TDs 2x (vs NYJ, vs KC). KC also hasn't given up more than 20pts at home this year (Phi, Was, Pit, Den, Buf) but that's with Peters.
I'm thinking I may have to trot Ryan out 1 more time and hope he puts together his best game of the season. I haven't made the playoffs in this league, yet. If I win this week, I'm in. If I lose, I'm out.
Edited: Cooper may play.