Which then led the GOP'ers in the room to say...uhhh...as they all had flashbacks to the 1980's.

Right....and then she backed off that position. She then pivoted to an agreement that immediately provided for border security funding and revisions to the green card program.

Again, your timing is off. The sequence of events was:

1) Feinstein asked for the clean DACA bill.
2) The GOP reps in the room said no.
3) The Gang of Six reached a bipartisan agreement between Republicans and Democrats for a framework that would address DACA, border security funding, and revising the green card lottery.
4) Miller and Kelly brought in the immigration hardliners who killed the deal.

Note how the bipartisan agreement was after everyone had already moved on from Feinstein's proposal. Her proposal didn't kill the agreement - the agreement came afterwards. It was the hardliners that killed the agreement.