@rrd2 you should take a close look at your whole data structure. You have duplicate IDs in both tables. Question is this what you want to have. This might bring all sort of problems in the future especially if you have cross-joins. I would advise to think about this from your business perspective.
The point with your data: it is the case that for 4,351 IDs from the (right) production data there simply is no match in the “Cal” data. I think you should take a serious look at your data stream and concept. I do not think it has anything to do with a KNIME node or function.