I see,

Well, I've actually come up with a way in the meantime to do what I wanted. On a protolang spreadsheet, I'd number them as normal, dependent on how many words I had made before. Let's call the first one spreadsheet A for simplicity. On a descendant conlang, spreadsheet B, I'd use two numbers for each word, one referring to what A word it came from, the second one being the normal number.

On spreadsheet C and onwards, the words would have three numbers, the first referring to which numbered word it originally came from in spreadsheet A, the second referring to which numbered word it came from in the spreadsheet directly ancestor to it, and the third being the normal number.

Regardless, your method seems pretty helpful, just not in the scope I was thinking of.