Sounds like you have both organisational and architecture problems here. A data team of ten and you're the only permanent employee? There's no data engineer or infrastructure team you can liaise with? I would discuss this with management, making the problem clear and that you're happy to help bridge the gap, but they need to hire someone with these skills.

For the software side Presto or AWS Athena will give you an SQL query layer over parquet files in S3, which should make life a lot easier. It will also hold the table_name -> s3_path relations. Lower effort than dumping to postgres, though at the current scale that is an option too.