Imho it doesn't make much sense to invest time in investigating closed-source related issues. For a matter of fact an experienced trader will not run a closed-source EA on a live account, so the questions and ideas are purely theoretical.
Instead I would focus on the real issue. Why do you have the need for redundancy in the first place? Obviously, as you stated, your server is of low quality. So, this is the issue to fix, and the issue can be fixed easily. For less than $50 you get 99% uptime garanty, so this should be fixed first. Setting up two low-quality servers trying to watch each other will not improve your situation but only cause sleepless nights. Do setup one high-reliable server, and setup bullet-proof monitoring and signaling for this one. That gives you an idea of how many outages really occur, and gives you a way to manually intervene. And manually intervene you will have to, that's for sure.
Manage your stops invisibly, and use visible desaster stops. That gives you a time buffer for manual intervention and the real safety net.
Instead I would focus on the real issue. Why do you have the need for redundancy in the first place? Obviously, as you stated, your server is of low quality. So, this is the issue to fix, and the issue can be fixed easily. For less than $50 you get 99% uptime garanty, so this should be fixed first. Setting up two low-quality servers trying to watch each other will not improve your situation but only cause sleepless nights. Do setup one high-reliable server, and setup bullet-proof monitoring and signaling for this one. That gives you an idea of how many outages really occur, and gives you a way to manually intervene. And manually intervene you will have to, that's for sure.
Manage your stops invisibly, and use visible desaster stops. That gives you a time buffer for manual intervention and the real safety net.