I think I've shared with you almost exact same thing happened to me only it was a such a massive starting lineup call I finished in the teens.
I sort of hate when people after the fact moan about a lineup call they did not make when they never really considered starting that guy they just lament it after the fact so let me be clear this was one legit lineup call.
Mahomes(QB1), Kittle(TE3), Antonio Brown (WR2) Michael Thomas(WR3), Mike Evans (WR9), Amari Cooper (WR17 on season but WR9 since trade from Raiders), Nick Chubb(RB8 since mid-season when they got rid of Hyde) made up all but one member of my starting lineup and all of those players were healthy and available all 3 weeks. My 5th WR was a spare and I was not benching Mahomes or Kittle so really nothing to think about.
My one lineup call was Sony Michel or Derrick Henry which had to be made on Thursday, what would be the game were Henry went nuts on the Jags so I obviously chose wrong. Friend of mine actually called me right before the game started because he had same lineup call in his local league and he called to ask for advice. I told him I was just sitting their examining the same thing and I was going withi Sony and he said he was not sure, that he was leaning Henry. He was explaining why he did not like Sony and the game kicked off and I remember us both say well to late now.
That one decision cost me $247,000.