@Alexandre_Rayes, indeed, the enriched event has 3 extra properties (when comparing with the shredded event) as per the diagram here (see 2nd image): https://github.com/snowplow/snowplow/wiki/StorageLoader. You can see the structure of a Snowplow enriched event here: https://github.com/snowplow/snowplow/blob/master/3-enrich/scala-common-enrich/src/main/scala/com.snowplowanalytics.snowplow.enrich/common/outputs/EnrichedEvent.scala#L41-L249. Though not sure if that would be the same as data are expected to be loaded to S3 with S3 Loader.
To query good data in S3 with Athena you can follow this guide: Using AWS Athena to query the 'good' bucket on S3