Cannot use Shortcut on EC2 Mac instances

I apologize, but there seems to be a misunderstanding in your question. EC2 Mac instances are not designed to run graphical applications like Shortcuts directly. These instances are primarily intended for building, testing, and publishing applications for Apple platforms in a cloud environment.

EC2 Mac instances are bare metal instances that do not use the Nitro hypervisor, and they are optimized for command-line and development tasks rather than running macOS desktop applications. They are typically accessed via SSH or other remote access protocols for development purposes.

If you need to run macOS desktop applications like Shortcuts, you would typically do so on a local Mac machine rather than an EC2 Mac instance. EC2 Mac instances are meant for tasks like compiling code, running automated tests, or performing other development-related activities that don't require a full graphical interface.

If you're experiencing issues with a development task on an EC2 Mac instance, it would be helpful to provide more details about what exactly you're trying to accomplish. There may be alternative approaches or command-line tools that could help you achieve your goal in the EC2 Mac environment.
Sources
Amazon EC2 FAQs - Amazon Web Services