I’d be OK with two options:
Sit tight at #13 and if Kyler Murray is available, draft him. Build around him, which then doesn’t require tanking.
If Murray is gone by #13, draft the best player defensive available or try to trade back for additional picks in 2020. Trade X Howard after the draft for the best possible return (hopefully a first-rounder, but more likely a second-rounder in 2020). Re-sign Osweiler for minimal amount. Let him start a few games, then switch to Falk. Let the chips fall where they may, record-wise. If we go 2-14, we’ll be in position to get a franchise QB. If we finish 4-12, we’ll have the draft capital to attempt to move up to select the QB. There’s the potential there to end up with three first round picks in 2020 (if you trade out of the 13th pick this year for a first-rounder in 2020 and find a way to get a first for X Howard).