Conversations with reconciliation experts suggest that the minority can in fact flood the zone with amendments--but it also shows that Democrats can circumvent them if they want to.
Let's say the Republicans offer 100 politically charged amendments to the reconciliation bill, none of which are germane. Democrats can move to waive all of them, and, as the Republican aide said, the minority can force a vote on the motion to waive.
But it's important to remember: Reconciliation is intended to be an expedited process. It allows for 20 hours of debate, after which all amendments must be disposed of in a so-called "vote-arama." So all of those amendments (or motions to waive the amendments) must be voted on in rapid succession.
The grey area lies in exactly how Democrats can force an end to the charade once its clear that the Republican tactics are dilatory. That's uncharted territory--but, as one expert points out, the chair in the Senate--a.k.a. Vice President Joe Biden--has almost unlimited power to make rulings so long as 50 members are willing to go along with them. And if Republican tactics were to go over the line, Democrats would theoretically be able to put a stop to them.
As former Senate Parliamentarian Robert Dove has pointed out, both the Republican strategy, and the Democrats' way around it, are far outside the traditional uses of the reconciliation process. But, hey, if both sides are exploring the limits of the rules anyway, who knows what will happen.