Encounters seem incomplete for gen3, missing npc trades

It seems that npc trades are not in the encounters data for at least the gen3 games.
Steps to Reproduce:

query samplePokeAPIquery {
  pokemon_v2_version(where: {id: {_eq: 10}}) {
    name
    id
    pokemon_v2_encounters {
      pokemon_v2_encounterslot {
        pokemon_v2_encountermethod {
          name
        }
      }
    }
  }
}

2. Observe there are no npc trades, despite there being npc trades within the game to get certain pokemon.

Start by tracing the pokemon_v2_encounters data behind the provided GraphQL query for gen3 games and compare it with the NPC trades available in those games. The work is done when the relevant NPC trades are represented in the encounters data and the sample query returns them.