If the Nest WiFi Point is reporting a weak connection, it may just need to be placed closer to the primary Nest WiFi Router. They connect to each other using a 5GHz WiFi link, so for optimal performance, it needs to be no more than one or two rooms away from the primary. From there, it will provide both 5GHz and 2.4GHz coverage to more distant clients.
Your clients should only see one network provided by both the primary Nest WiFi Router and secondary Nest WiFi Point. They will decide which one to connect to.