Infinite Scaling of Selenium headless .jar tests using AWS Lambda

Current State I have a gradle Java 11 project (.jar file) that uses Selenium and TestNG to test several web applications in Google Chrome; for each web app one end to end test case is executed. This .jar file runs in a docker container on a Windows Server and it executes the test cases sequentially.

Desired State I want to run all the test cases concurrently or in parallel where each end to end test case would execute in it's own AWS Lambda Function. Furthermore, I want my set up to allow for the AWS Lambda Functions to scale out or in horizontally depending on the number of end to end test cases that are added or remove in the future. I am trying to figured out how to best approach this.

Possible Solution Should I use an AWS Lambda Function with the Java runtime and the AWS RequestHandler.java or should I use an AWS Lambda Function container.

Questions How do I dynamically spawn off AWS Lambda functions? How do I gather all the TestNG test case reports? Should put them in an S3 bucket?

Reference or Context The following link is the closest one explaining the bigger picture of what I am trying to achieve https://aws.amazon.com/blogs/startups/infinite-scaling-of-selenium-ui-tests-using-aws-lambda/