This would be hard work to do this programmatically, or even with formulae, however, in the attached, not quite what you asked for, but relatively easy to obtain, is a pivot table next to your expected results.
This pivot is based upon a new consolidated table in a sheet Lab&Cost. You can see how this table is made from your two dumps. Each month you'd add to the bottom of the Lab&Cost table.
This monthly process could be automated (in fact, if you made this table a proper Excel Table, after adding the data you'd only need to refresh the pivot).
Note I've added a comments column which would allow you to keep the comments month to month.

It's only an idea, but to get exactly what you want I think people here wouldn't be prepared to spend the time necessary to do it (you watch, having said that, someone will do it!). I think you'd have to pay someone to do it.

Edit post posting:
Grrrr. Cross posting without links AGAIN!
Attachment removed until sv29 complies with rules.

Edit2 post posting:
Attachment restored to this message.

Attached Files

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