"This seems to be just a regular pre-tax 401k deferral for tax year 2022"

While it can be repaid to a different employer, or even an IRA instead of a 401(k), that isn't what is being attempted here.

You can't repay the distribution as a rollover, amend the tax year for purposes or otherwise not have reportable income from that distribution, and then also get a pretax benefit of that rollover. Reporting it as taxable, then getting to exclude it by repayment, are the offsets of each other. Also making the repayment from pretax funds is the double-dip.

Did he tell the employer this is what he wanted to do? Their plan would need to accept this type of rollover; it's not a given.