2 major challenges for which JS comes as a handy tool, 1st its integration with AWS SDK was at par as Python and .net and the solution comes to hand with the reverse proxy solutions for the application to be running as an instance taking the situation of inside organization demography of resources expertise over the technology.
You must have gone through multiple thoughts on how to handle the requirement, but the biggest problem that I am able to see here is a dependency on a certain platform for executing Powershell scripts. Next is being a developer will never suggest having Powershell or bash as a backend of your system until it is related to some IoT Stuff. In place of it, I would rather suggest you use Infrastructure as a Code that comes with terraform or Ansible or as your application is based on Azure so u can use Azure Resource Manager too.
Adding to it for making config or attaching a trigger to these infrastructure controllers, you can use lightweight stateful APIs with the help of flask or express or go-mux, to keep track on the progress of deployments.
