To follow up on this post:  I called Intuit and they are totally hung up on this being about the 3rd Party app.

This is a new client and I have fixed how the 3rd Party app sends over the income and payment entries.

The 3rd party app is totally irrelevant at this point.  A human being could have posted these journal entries.

The POINT is:  how do we clean up hundreds and hundreds of journal entries hitting A/R over several years WITHOUT having to click on each and every single entry in the "Customer Payment" screen?

HOW the journal entries arrived in QB does not matter.  Forget that I ever mentioned a 3rd Party app.

All that matters is that it will take WAY TOO MUCH TIME to click on every single entry to get this fixed.