My RAK7249 GW is registered on v3. I set the location manually on the V3 console.
When I go to https://www.thethingsnetwork.org/map the GW shows but the altitude showing is not what I inputted into v3. The altitude is from the GW itself. The GW is set to public in v3. To reiterate the configuration in V3 is set to manual.
I have followed the documentation for TTN Mapper for v3. The webhook is in, JSON objects for lat/long exist. But TTN Mapper shows nothing. I have checked in TTN Mapper using advanced maps with the end device id and GW ID.
AFAIK TTN Map does not show V3 GW’s - yet! What you may be seeing could be the old V2 GW which will ‘age off’ the TTN Map after it is not seen for ~30 days. As you will appreciate the TTN Map and TTN Mapper are not the same thing, good to see you testing out @jpmeijers temporary webhook ‘fix’ for v3 on TTN Mapper until full integration and template in place. Perhaps he can advise on that side.