Automatic element clicker with multiple google instances (up to 60)

The website is [login to view URL] (you might need a UK/western europe/USA VPN to access it), and it allows ads to be reposted every 15 minutes. I have around 40 accounts with one ad on each that need to be reposted at different intervals, because if they're all reposted at the same time, some of them won't get to the first page. So that means the would need to log in to the account, navigate to the 'my account -> my ads' and focus on the 'multi repost' button. I already use a web extension called Wildfire, but I can't scale it. I have virtual machines from Microsoft but they get very expensive because I can only run 3 accounts on one machine (the extension is only compatible with Chrome, Firefox and Edge), and they also eat up a lot of ram for one machine to handle, so it sometimes crashes. Let me know if you need more detail. I need this done as soon as possible. I'm willing to pay extra for a job well done, if you can do it quick.