If you follow the instruction with the Intune Integration, what you need to do is enroll the device into intune. Once enrolled into intune, the device should be in an appropriate device group (in Azure AD). From there the app and app config will be pushed. In short, the workflow should be:
1. enroll device into intune
2. the app will auto-installed and show up
3. user click on the app, choose intune login. Then accept the user notification or OLP setting.
With intune integration, you don't need separate activation email. Intune will mark device compliant only if device have sandblast mobile installed(and activated) through the compliance policy. And if device is not compliant in intune, you can restrict the device access to corporate data (such as setup custom conditional access in Azure).