Its not obvious to folk who arent regular forumites or users that packetbroker is a way forward, especially in light of old V2 services tied to the old “noc.theth…” so OP can be forgiven for not getting that straight away. Closer to old system using V3 instance is to look at queries targetting variation on “https://eu1.cloud.thethings.network/api/v3/gs/…”
e.g. taking same gw as example - https://eu1.cloud.thethings.network/api/v3/gs/gateways/g-s3-testgw001-ttkgw-hp10/connection/stats