It’s a bad things because both bills go to a conference committee made of House and Senate members that works out any differences between the versions. The House version would almost certainly be gutted. Then the consolidated bill goes back to the House and Senate for final approval by simple majorities. In the House, that means all Democrats and a handful of Republican traitors pass the bill.
https://en.wikipedia.org/wiki/Reconciliation_%28United_States_Congress%29
Reconciliation is supposed to be for budget bills. I think you mean it would go into conference.