There is no available API that allows you to connect to Android. The current APIs that are provided are not compatible outside of the Apple Ecosystem. For example, Android requires you to set a service name and a password where iOS sets a service and a PIN authentication strategy in a specific format that’s not compatible. It looks like the implementation is not following the Wifi Aware Specifications.
To enable cross platform interoperability while providing security, could you adopt the same strategy as with Bluetooth and enable iOS users to enable the sharing and subscription of services with Everyone.