But there is: it's called the Constitution. Not any particular clause or article, but the whole document. The executive is allowed to check the judicial if the judicial ignores the Constitution. How else is the executive supposed to check the judicial?
> It would be a VERY BAD precedent to do that again.
It would be a bad precedent, but it would be an even worse precedent for the Supreme Court to force the government to default on its debt. The least bad of the two evils would be for the government to continue paying its debt by waving the debt ceiling away.