It will be interesting to see if those accounts had any discussions together, owning so many accounts it's easy to create conversations between them and make those posts counts per week quite quickly. In addition it will be just another nail in the coffin of the "I have only one account" statement.
When post count is the only thing in mind then anything can be possible. Creating conversations between their own accounts could be only one of them. Imagine you are required to make make 125 posts a week. That's 17 to 18 posts per day. If you are spending 8 hours then 2.25 posts per hour. Wait! It seems an easy job LOL.
The only problem I see that you can not have a day job and you can not have a weekend. You miss one day, you handle the pressure of additional 18 posts on your shoulder for that week 🤣