Husband's Calorie Intake

There are men who need that many calories, and a few who would lose weight on that many calories.

Since you've told us nothing about your husband's age, height, weight, job, exercise, and that sort of thing, it's hard to confirm that that's "insane". I admit that's a high number, but we see people here posting fairly often that their calorie goal is too high when it really isn't . . . they're just under the misimpression that tiny calories and general misery are necessary for weight loss.

As for what to do, one thing is the advice above: Check all the data in his profile entries for accuracy. It's easy to make a typo.

Another option would be to put his data into a good TDEE calculator, and see how many calories it estimates he'd need to maintain his current weight. Personally, I like the one linked below because it has more activity levels than most, and the descriptions are clearer, plus it lets a person compare multiple research-based estimating algorithms. That last might be particularly helpful in a case like this.

The page looks complicated at first glance, but you won't have any trouble using and understanding it if you step through it systematically, and there's lots of good info there.

https://www.sailrabbit.com/bmr/

From the maintenance calories, subtract 500 calories per day for each pound a week estimated loss, or 1100 calories per day for each kilogram a week estimated loss. Something around half a percent of current weight per week is a reasonable and moderate loss rate; anything over one percent of current weight per week is suitable only if severely obese and under close medical supervision for nutritional deficiencies or health complications.