I agree with the above comment. Running multiple Google maps does not work. However, you can have multiple maps visible, so long as only one is active at a time. What you do is:
- Capture and optimize a screen shot of each map.
- Decide which one (if any) will be the default map. Note: Your initial page load is faster if none are active by default!
- Display the default map (if any) and use the static images of the others as graphical anchors to animate the respective map.
You can achieve the swapping of the active map by using separate web pages, one for each active map, or by using JavaScript. I'm old fashioned and use the separate web page approach.