@Ohad 

Hi, Welcome to the community.

As for the second issue, since I didn't have M9 plus, I tested on M4 and I could both initiate and receive a call from IPad(without SIM) when it is on the same Wi-Fi as my iPhone.

Since I only had one unit for the test, so could you please try to check whether you can initiate a call when iPhone and MacBook are connected to the same Deco, the same wireless band?

For the first one, I might need your help to get more details:

1. Did any of the internal hosts failed to ping each other, like ping the iPhone from your Mac, or ping Deco LAN IP from Mac?

2. Did your M9 plus work on wireless router mode, or access point?

3. Have you enabled any guest network?

Thank you very much and wait for your reply.