One of Kagi's pillars is privacy, but the maps tab doesn't use first-party map data, instead, your query is sent to Apple and your browser connects to Apple servers to request map data. Apple is a third-party, so it would be better to let the user know, sort of like DuckDuckGo does with YouTube video embedding, or proxy it.
A dialog that says, "Connecting to Apple Maps [description] Kagi uses Apple Maps while Kagi Maps is in beta. Your query and browser data will be handled by Apple Maps during your maps session. [Confirm?] [Deny]" would suffice.
This dialog would only show up once.