Hector - FIXED. It was due to the Elementor plugin's latest version not being compatible with the theme.

I knew it. Kind of figure it had something to do with a plugging since something similar happened with another client. Is there a way to make sure this does not happen? The site was down for more than 16 hours because of this.
And thank you for taking care of it Isaac  

Hector - Unfortunately not much other than act as soon as the site reports a critical error on the website or disable automatic updates and manually update the plugins after every month or so.

We can add a custom code that will disable the automatic updates for the elementor plugin but when the theme or wp-core files get updated automatically it can cause compatibility issues.

Also if we add a custom code that will disable the automatic update for all the plugins + theme  + wp-core files on the website. It will make the site vulnerable to site attacks in the near future. 

Since this website is hosted with the wpengine hosting. We can try with their smart plugin manager that automatically reverts the plugin to its previous version if the new version creates a critical error on the website. 

https://wpengine.com/support/smart-plugin-manager/  

Either way is an issue huh? Luckily we got that Uptimerobot tool to help us keep an eye out for these issues. We can leave it as is for now. I will run it by Chris and see what he thinks about it. 
Thanks for the detailed explanation by the way. 
You're awesome!