Sometimes it’s tricky to assign blame on shutdowns. Maybe one side wants $4.2 trillion and the other side wants $3.8 trillion, and so it’s just a stalemate. But when one side wants to add non-appropriations to a measure and the other side rejects those, it seems the side demanding the policy riders fairly gets the blame. This is why Ted Cruz got the blame for the 2013 shutdown: his “defund Obamacare” measure was legislative in nature, and not merely appropriations.
In this case, the DACA folks are the ones demanding a non-appropriations measure be tacked onto an appropriations bill. They’re using the threat of a shutdown as the lever by which to achieve their policy goals.
The thing is, they could, next week, perhaps use immigration policy as a lever by which to get a DACA fix. Say, build a wall and make a plan to end chain migration. But they’ve decided if they are going to pay a price for DACA, they’d rather it be shutting down the government.