Democrats absolutely cannot just fold when McConnell puts poison pills in legislation like this.
There are two decent choices.
Vote for it anyways, with all democrats voting for it.
Vote against it, with all democrats voting against it.
They are completely different strategies.
In either case, the democratic Senators have to explain loudly and to any news organization that will listen as to the reasoning behind the decision. And then Biden has to publicly support whatever decision the Senators go with.
And, ya know, what COULD happen is that the democratic Senators and Joe Biden could coordinate their efforts before the vote even happens.