My husband made an early withdrawal on his 401K when he was laid off suddenly so we could pay our rent, etc because he is the main breadwinner, a qualifying hardship?

The distribution will be taxed however the 10% penalty should be waived if you qualify : 

https://www.irs.gov/newsroom/coronavirus-related-relief-for-retirement-plans-and-iras-questions-and-answers

General "hardship" is not an exception the the 10% early-distribution penalty.  To avoid the penalty he would have to qualify for one of the specific exceptions listed in the reference provided by Critter.