I'm also surprised of a change of ownership. As a quiet member of this group since 2016, I hope there the group will not go sideways. Thank you Tod Daniels and other admins and moderators for your great contributions on this group.
Immigration at the airport will not care if his passport has "cancelled stamp" on his extension.
The only problem he "might" encounter is when he returns and apply for an extension at the local immigration. They will overlook that he left the country and got a new visa. This is case to case basis (from one local immigration to another).. As they will see that he "left " the country 2 weeks after his permission of stay /based on a work permit" was cancelled.. he will be fined from the date his wp was cancelled until he flew out.
As advised, its better to go to the local immigration, have it stamped cancelled and apply for an extension due covid reason
if she got a multiple entry non immigrant b visa. she need to do border bounce. if she got single entry non immigrant b visa, she need to have apply for a yearly extension at the local immigration