Developing CarPlay Application for Emergency and Non-Emergency Services - Which Category and Template to Use?

I am currently working on an iOS application that provides a range of services, including both emergency services (e.g., fire, medical emergencies) and non-emergency services (e.g., patient transportation to hospitals). Now, I am looking to extend the functionality to CarPlay, and I have a few questions regarding the suitable category and template for CarPlay development.

CarPlay Category: Considering the nature of our application which covers both emergency and non-emergency services, I'm wondering which CarPlay category is most appropriate for our use case. Should we go for the "Navigation" category or another category that aligns better with our service offerings? Our application requires users to register cases for emergency or non-emergency services, and we provide services exclusively for registered cases. Additionally, we have predefined limited locations for pick-up and drop-off. Given these considerations, would the "Navigation" category be feasible for our application on CarPlay, considering the need for location-based services and step-by-step navigation to predetermined destinations?

CarPlay Template: I would like to know which CarPlay template would be best suited for our application. Are there specific templates optimized for emergency services or transportation services on CarPlay? If we choose the CarPlay Navigation category, the CPMapTemplate is available to render the custom map. However, for our CarPlay application, we plan to introduce additional features alongside map navigation. Specifically, we intend to set driver and crew member information within the CarPlay application. This includes vehicle details, crew member details, and shift timings for crew members. Our system assigns cases to a particular driver based on this information. The app flow we are considering involves using the CPTabBarTemplate, which includes 3-4 tabs for shift details, vehicle information, etc. One of the tabs will display the map for step-by-step navigation.

We have reviewed the CarPlay Navigation programming guidelines, which mention that on the base view, only the map can be rendered, and other UI elements cannot be displayed. However, in our case, the root template is CPTabBarTemplate rather than the CPMapTemplate. I am wondering if this approach could potentially create any issues during the Apple App Store approval process?

Our primary concern stems from our initial belief that the Navigation category, with its extensive support for built-in templates, would allow us to implement a TabBar. Our intention was to incorporate the CPMapTemplate within one of the tab items. However, this approach seems to contradict the CarPlay Navigation programming guidelines.

Step-by-Step Navigation: For the non-emergency services, specifically patient transportation, we need to provide step-by-step navigation for drivers while picking up and dropping off patients at nearby locations or hospitals. Are there specific CarPlay features or APIs that facilitate seamless step-by-step navigation within the CarPlay interface?

Must-Have Features: In the context of CarPlay development for emergency and non-emergency services, are there any must-have features or guidelines that we should consider integrating into our CarPlay interface, especially for step-by-step navigation during patient transport?

I appreciate any insights, experiences, or recommendations from developers who have worked on similar projects or have expertise in CarPlay development. Thank you!