Additional Metadata in API tracking events

Hello,
I'm trying to include additional account metadata ( name ) as part of the POST data.pendo.io/data/track API. I see there is a context object, but based on the documentation it does not appear to support metadata about the visitor or account.

Is this use case supported in some way with a Pendo_trackEventSecret_Key, or is PUT app.pendo.io/api/v1/metadata/:kind/:group/value/:id/:fieldName (and the other metadata endpoints) using PENDO_INTEGRATION_KEY the only option?

Thanks!