The Amp has no line-out to connect to your Receiver, either digital or Analog - you need a Sonos Port. See connections:

You can read more about the device here:

https://www.sonos.com/en/guides/port

So for zone 2, if i disconnect from receiver can i just connect to sonos amp to stream?

Yes, you could setup those passive speakers as a separate ‘Sonos’ room with the Amp, if you want that aswell. 

NB: The speakers’ power rating should be at least 125W for 8 ohm, or at least 200W for 4 ohm speakers. The manual says to not connect speakers rated at less than 4 ohm.

Thanks Ken. 
For the speakers that are 7.1, if i connect a Sonos Connect, how does it connect to the receiver?  Using which port?  Is there wifi capability on the connect?

PORT (or CONNECT) is a stereo (two channel) device. Attach PORT as if it is a cassette deck or, if your receiver does not support a cassette deck, attach PORT’s Line-Out to the receiver as a CD player.

Ok so with the Connect i can connect via wifi to stream music through my receiver and listen on non sonos speakers?

Yes, you can stream audio over WiFi, using the Sonos App, to the Sonos Connect, or Port, attached to your Receiver and play to the connected speakers.