Given that school budgets are absolutely gutted with mass layoffs this year and next, and the miscalculation looks like 2/3 of the budget shortfall, hiding such a basic and impactful error requires a much better explanation than I see in that article. It looks like it was done to stifle debate about budget allocations, which would be necessary in the circumstances.
The education system seems one of the only places where vastly improving technology over the past 30 years has not translated to cost savings or improved outcomes.
It shouldn't be surprising when you see what the educational technology money is actually spent on. Ive seen like a dozen "smart boards" purchased by my schools from the 00's and never once seen one used. Or how about the completely dog shit computer testing software that fails one-two word answers based on random capitalization or punctuation with no indication on what they expect. Each thing sold as the solution to all the past problems, but introducing more problems itself without actually solving any old ones.