You’ve been getting a lot of bad info on this thread — some good info, but too much bad.
I’m a pension actuary and I’ve spent my career helping employers design and administer defined benefit and defined contribution plans. 401K plans are defined contribution plans.
When employee and employer contributions are made they are put into a trust. Those contributions then are not affected by anything that happens to the employer. So, the future of the employer doesn’t affect the money that’s held in trust for your husband in any way.
An employer match of 50% is actually a pretty good plan.
It sounds like the plan vests 100% employer contributions that are in the trust, or plan, for 2 years. That’s a pretty good vesting schedule. That means that employer contributions that have been in the trust for more than 2 years are your husband’s. Employer contributions made during the last 2 years would be forfeited upon termination of employment.
It sounds like either the HR person was communicating incorrect info in some respects or your husband wasn’t understanding fully what was being communicated.
In any event, your husband should have been given a Summary Plan Description that explains the plan, and he has a right to a copy of the actual plan document if he requests it.
An attorney shouldn’t be necessary. That would almost certainly be a waste of money. I seriously doubt that the company or the HR person would try to cheat you. There are very serious potential federal penalties if they did.
How does that work if the fedgov says you are to be 100% vested at six years? Is it a moving target? My understanding was that once you hit the 100% vesting target date, 100% of what was in the account was yours, both your contributions and the employer's, both past and future contributions.