Recess appointment.
They may think they can beat Trump on this one but FAFO very much applies.
The nice way: let Trump have RFKJ by a party line vote.
The other way: Trump uses a recess appointment to put Bobby in despite them, and Elon and Nicole Shanahan create a PAC that will spend however much it takes to defeat them in their next re-election. They can make it very expensive, very intense, and very painful and in the end they will likely lose their seat. Even the dumbest Senator will be able to grasp the financial risk a NO vote on RFKJ will have.
I think Trump will use every option for RFJK, Kash, and Tulsi.