Then do you count emissions from Microsoft's suppliers? This announcement says they are considering emissions from their entire supply chain, so I can't imagine a reason why this wouldn't also apply to people they pay to work for them.
I believe that this is addressed in their "Scope 3" section that is mentioned, and they are looking to cut that figure in half by 2030, and it is included in their "net negative by 2030" considerations.
They can tell their suppliers to be carbon neutral or lose contracts. But this is a free country, there isn't much they can do about the employees beyond what they're _already doing_, and have been doing for at least a decade now. I live in the area, you see MS buses all the time, and many of their employees use them.
All that "offsetting" is mostly for rich people to feel good about themselves as they fly their private jets to climate summits, it does little to nothing to reduce the actual CO2. Once that CO2 leaves the tailpipe, the only way to reduce it for real is by capturing it.