Don - agree with you that adding column does not break the model. It just any query that uses these extra columns would naturally not work across multiple organizations - but not users of OMOP CDM use it for the purpose of network studies. ATLAS would not also be able to take advantage of these extra fields. So, people just need to be mindful of the limitation of using fields that are not a part of the OMOP CDM standard but there are some legit use cases.
In Jose’s case, they are adding some extra columns that carry extra info - and I will let Jose share this information - and those are being used by internal teams, including for traceability back to the original source.