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There's Euclid, which maps out the visible sky in insane detail [0]

There's Galileo, which provides much higher accuracy than GPS. (20cm vs 5m!)

And then there's Copernicus, which provides open-access Earth Observation as a public good.

[0] https://www.youtube.com/watch?v=86ZCsUfgLRQ

Let's say you need to start the burn within a +/-10m box to come to a stop 1 to 21m above the moon surface. You want a sensor with something at least 10m precision but preferably more like 1m. That would be the radar. But then say you have something like a GPS with +/-100m precision. Does that help? Your safe window is somewhere inside that 200m but you cannot be sure where until the radar comes online. So do you use the +/-100m info from the GPS? Do you maneuver to center yourself inside its error bars? All you can be sure of is that you are somewhere within that 200m and are 95% sure you are not within the 10m window. So you make a maneuver anyway. Are you now in any better an information position? No. You are still somewhere in the 200m box and are still very likely outside the 10m box. Heck, you might have been inside the 10m box and just moved yourself out of it. You just wasted fuel. The only logical thing to do is to ignore the GPS and wait for the better/actionable information from the radar. The GPS may give you a warm fuzzy but it doesn't actually help when you only have one shot at the burn.

(This problem is mirrored in areas like missile guidance. Running parallel sensors on a missile sounds like a good idea but in reality leads to confusion, wasted energy/range and reduced chance of getting to the target.)