If the app is down and the votes are being tabulated manually, can it be blamed for the mistakes being identified by NYT?
The app is a problem for sure. The state party obviously thought (rightly or wrongly) that it was worthwhile to seek out a tool to automate some of the more demanding aspects of the new rules. Its development, testing, training, implementation, and reliability are all worth examining. But it's also a convenient scapegoat for the process failures of a dumb-to-the-point-of-being-undemocratic system for selecting a candidate.
As NYT points out, under the old method, discrepancies were hard to identify but relatively easy to fix. Here, they're easier to identify, but it still takes time to fix them, because it requires a lot of assessment around exactly where the errors lay. I don't begrudge Bernie's campaign at all for seeking transparency in the process. I do think it's disappointing to see the howling on Twitter about dirty tricks and an unjust system when the very demands for transparency are part of what is causing the problem. Own it; trust the process. A simple statement would go a long way: "We've known since 2016 that changing the way the Iowa caucuses operate would be challenging, and it's certainly frustrating that this delay has occurred. But we have faith that the safeguards and transparencies built into the system will ultimately provide us with more accurate data that we can all have confidence in." Selling the people that if you're not winning, it must be because the system is somehow disenfranchising you, may end up being a path to victory, but it does nothing to strengthen the institution of democracy.