Have you told them (or have they been told) that they can work from somewhere besides there home?

Obviously there is an exception right now, but normally "working from home" means you can work from anywhere you want (different country, parents cottage, coffee shop, outside, where ever).

I work for a tech company and we have people who regularly go to Europe/other places for months and work from there just getting up/working later depending on timezone.

Most people assume that working from home or working remotely means sitting at home at a desk and working the exact same as you would an office. In which case you lose the office communication. But that's wrong.