How to add runtimePlatform config on ecs:push work pool

I am using a esc:push workpool and I want to update the “runtimePlatform” task definition configuration to use “ARM64”. However, my deployment is crashing with the below error message.

Flow run could not be submitted to infrastructure: list index out of range

I have attempted two different approaches with both failing.

Method 1:

Adding the option to the advanced section of the work pool options:

  "runtimePlatform": {
      "cpuArchitecture": "ARM64",
      "operatingSystemFamily": "LINUX"

Method 2:

Creating a task definition on ecs and supplying the ARN to that task definition option of the work pool option.

Any help is appreciated.