How to integrate Bluetooth Scanner into Xamarin App on Non-Zebra Device


I've installed the Zebra Scanner Control App on a Nexus 9 Tablet (Android 7.1, API 25) and was able to connect to a DS3678 scanner.
Now I would like to be able to scan from my Xamarin (Forms) App. EMDK for Xamarin does not work because it expects some infrastructure that is not present on Non-Zebra devices.
I've create a Xamarin Android Bindings Libray (Xamarin) in VS2017 around the "barcode_scanner_library_v2.2.4.0.aar" and was able to compile and build it successfully.
If I try to instantiate the central Class SDKHandler I get an exception "ClassNotFound".

I'm stuck here. Is there anybody that tried something similar and succeeded? Are there any working samples available?

Thanks in advance for any help

Best regards