SageMaker Neo Object Detection Compilation Job Failed

I have a custom trained object detection network to detect the License Plates of Vehicles which I am trying to optimize for deployment on Nvidia Jetson Xavier by performing Neo Compilation. The framework used is Keras.
I have compressed the model.h5 file which contains the weights & architecture into model.tar.gz and uploaded it to S3.

I have run multiple compilation jobs but all have failed stating the following message:
"ServerError: There was an internal server error during the compilation job, please try again in a few minutes or contact amazon-neo-feedback@amazon.com to get support for this compilation job."

I was hoping to get answers to few of my questions:

Q1) Does Sagemaker Neo support Object Detection models?
Q2) If yes, then does it support compilation of pre-trained OD models ?

My data input is of the shape: (1, None, None, 3) where a "None" dimension signifies that it can be any scalar number. I have tried giving SageMaker Neo's Data input configuration as {"input":[1,3,null,null]}, {"input":[1,3,224,224]} however it still fails with the same error mentioned above.

Q3) What is the correct way to input the input configuration for OD models where the width,height dimensions can accept any values?