@Matthew_Raleigh2 with headless SDK, you are responsible for building the UI components, so adding/removing typing area is entirely up to the your logic within the custom client. Not sure if I mis-read your request.
To be clear: if you want to use "headless" mode, you would be turning-off the native Messenger UI from the corresponding Messenger Configuration.
Trying to control the native Messenger UI via commands/events (which is valid approach) is different than using "headless" mode. And the native Messenger UI doesn't have any command to remove typing area.
Both are valid and provide equivalent feature coverage. #1 is somehow "easier" in the sense that it will natively take care of network connectivity, and is a wrapper around #2.