EXACTLY, this happened to me/us
I agree. I had a "mailing list" that was part of a business group, and some of us were getting spam emails that appeared to be from one of the group, but as it turns out, the computer guy in our group was able to confirm that the computer that was sending the emails was NOT what was showing in the emails.
In other words, the supposed sender was not even in town at the time of receiving the email! His computer was OFF.
The actual "drone" computer was cleaned out and problem solved!