The voice recognition API is part of the Google Mobile Services (GMS).
The MC67 is based on AOSP (Android Open Source Project) and doesn't come with GMS.
So answers to 1. and 2. are "no".
Andreas, thank you for the reply. However, and as information to all, I found a way around this. Probably not going to be blessed by Zebra BUT, I was able to get my hands on the apk for the GoogleQuickSearchBox, namespace is com.google.android.googlequicksearchbox. See here for the application: https://play.google.com/store/apps/details?id=com.google.android.googlequicksearchbox
You can find apps that will extract the apk from an app that you download from the play store.
I then simply installed the apk, as you would any other app. After that, I had full speech recognition, not only accessible in my Xamarin application but also in the Google Now search bar.
Hope this helps.
Please be aware that proprietary Google software is subject to Google's licensing terms and conditions.
When you use that software, make sure, you are not violationg any of those.