AWS - CloudFormation "Waiting for association to be applied."

I am working on rendering optimization for our project, following this tutorial: https://ec2spotworkshops.com/rendering-with-batch/start/on-your-own.html. However, it is outdated, and I am struggling to make it work. I had to update the

 stack.yaml

by adding an

ImageId

to get it started, but now it always times out on "Waiting for association to be applied." Has anyone ever seen this issue? I tried searching the web and ChatGPT but couldn't solve it, so I am trying to ask here. Any help appreciated.

P.S. There is nothing new in the CloudWatch logs