Star Trek is one of the highest costing shows production wise on TV. They aren't squirreling away money, it's getting spent on other production costs. Contractors and EFX artist ain't free.
They had a budget, the sfx was probably mostly done, and then they fired Wang for a couple episodes. It was magical found money that could have gone anywhere if everything hadn't already been paid for... But after the rewrite it was probably used to pay for Alexander Enberg to pretend he was a full cast member that week.