There's been some pretty clear suggestions up thread on where to find the funds, namely "several months ago in the past". To be more clear:

The business (Convoy) should have shut down in e.g. August of 2023 when it was clear that they still had enough cash to pay out severance and still cover the expenses of winding down the business. They did not take this option, choosing to instead risk it all that they could bring in an infusion of cash without firing folks.

This is not "boilerplate vapid moralizing nonsense"; to take such a risk when you have a company of 500+ employees is a poor business choice.

Everyone knew the writing was on the wall 4 months ago when they were shopping for buyers and laid off 1000 people.

The fact that they continued to operate for 4 months with no new investment is the same as if they had shut things down then and offered severance.

There was no gamble here like your comment implies.

If you can find out where it says companies are obligated to pay severance or other benefits to employees in the US, I'll eat my hat.

Smart business choices rarely align with choices that I benefit employees.

Well, back in the old days, they did just that and called it a pension plan. Takes a little foresight and is too little too late for convoy of course, but these things can be planned for too but clearly the worker is not prioritized in these ventures.