They had 50 votes to get rid of the filibuster in its entirety. It's such a convenient cop-out for Dems to say "ah gee whiz, we have 2 turncoat senators, so we can't get anything done." Even if they had 60 senators, they wouldn't've passed anything because of their commitment to "bipartisanship."

They just didn't. I'm as frustrated as you but to change the rules they needed 50 votes and if you start out with 50 and have two turncoats, then you only get 48. You can yell at them and offer stuff, whatever. But ultimately they decide how they vote and if you don't get to 50 you lose.