I'm seeking clarification on the lounge access rules for the Air Canada Maple Leaf Club given my situation:

- Departing next week, going from SFO-YYZ-BOM
- The SFO-YYZ is operated by United and YYZ-BOM is on Air Canada
- Flight was booked on United.com
- We are a group of 4 pax: 2 adults and 2 children (10 and under)
- I have the United Club membership via the Chase Infinite credit card
- I also have United Gold status which gives me Star Alliance Gold

My understanding is that I can bring one adult guest to the Maple Leaf lounge and that young children are free as long as they are accompanied by an adult.

Here are my questions:
1) Is my understanding correct? Or should I purchase a maple leaf lounge pass in advance?
2) Will I be able to access to the AC MLC in SFO and YYZ?
3) Assuming everything above is true and valid, which MLC lounge in YYZ is the best one to visit?

Thank you in advance for your help!