Changing the color of a custom annotation

I am creating an app to show user locations on a single MapView. Within the app, the user is able to place down an annotation by tapping the screen. This annotation is called my CustomAnnotation for plotting a route from their location, to that dropped pin. Now, I have created another annotation class called MemberAnnotation. I created a pop-up button that will allow the user to choose how they want their annotation color to look. I have already created an extension on UIColor to convert a UIColor's RGB values into a string, save that string to FireBase, and convert the string back into a UIColor when fetched. Now, I just can't seem to figure out how to customize each annotation for the specified member.

I have created a function to customize the routing pin:

func setupCustomAnnotations(for annotation: CustomAnnotation, on mapView: MKMapView) -> MKAnnotationView? {
    annotation.title = "Route"
    
    let view = mapView.dequeueReusableAnnotationView(withIdentifier: self.routeIdentifier, for: annotation)
    if let markerAnnotationView = view as? MKMarkerAnnotationView {
        markerAnnotationView.animatesWhenAdded = true
        markerAnnotationView.canShowCallout = true
        markerAnnotationView.markerTintColor = UIColor.black
        btn.setImage(UIImage(systemName: "location"), for: .normal)
        markerAnnotationView.leftCalloutAccessoryView = btn
    }
    return view
}

And I am calling it in my MapView Delegate:

extension MapHomeViewController: MKMapViewDelegate {
func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    guard !annotation.isKind(of: MKUserLocation.self) else { return nil }
    var annotationView: MKAnnotationView?
    
    if let annotation = annotation as? CustomAnnotation {
         annotationView = setupCustomAnnotations(for: annotation, on: mapView)
    }
    return annotationView
}

Just not sure what to include in the separate function, where to call, or if I even need to make a separate one? Any step in the right direction would be a massive help, thank you!

I ended up getting it shortly after making this post but forgot to post my answer! Here is the following code I wrote on the MKMapViewDelegate extension:

    func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
    var annotationView: MKAnnotationView?
    
    if let annotation = annotation as? CustomAnnotation {
        annotationView = mapHomeViewModel.setupCustomAnnotations(for: annotation, on: mapView)
        return annotationView
    } else if let annotation = annotation as? MemberAnnotation {
        annotationView = mapHomeViewModel.setupMemberAnnotations(for: annotation, on: mapView)
        return annotationView
    }
    return nil
}

And here are the 2 functions that I created on my ViewModel:

    func setupMemberAnnotations(for annotation: MemberAnnotation, on mapView: MKMapView) -> MKAnnotationView? {
    annotation.title = annotation.member.screenName
    
    let view = mapView.dequeueReusableAnnotationView(withIdentifier: "Member", for: annotation)
    guard let markerColor = String.convertToColorFromString(string: annotation.member.mapMarkerColor) else { return nil }
    if let markerAnnotationView = view as? MKMarkerAnnotationView {
        markerAnnotationView.animatesWhenAdded = true
        markerAnnotationView.canShowCallout = false
        markerAnnotationView.markerTintColor = markerColor
    }
    return view
}

func setupCustomAnnotations(for annotation: CustomAnnotation, on mapView: MKMapView) -> MKAnnotationView? {
    annotation.title = "Route"
    
    let view = mapView.dequeueReusableAnnotationView(withIdentifier: "Route", for: annotation)
    if let markerAnnotationView = view as? MKMarkerAnnotationView {
        markerAnnotationView.animatesWhenAdded = true
        markerAnnotationView.canShowCallout = true
        markerAnnotationView.markerTintColor = UIColor.black
        btn.setImage(UIImage(systemName: "location"), for: .normal)
        markerAnnotationView.leftCalloutAccessoryView = btn
    }
    return view
}

Hopefully this helps someone out later on!