Expanding Merged Query to select desired columns pulls in duplicate rows of data

1. I am using one Excel workbook, connecting to Power BI and pulling in 3 worksheets.
2. Two of the worksheets have exactly the same columns, just different rows, so I used Append to put them together
3. Great, Power BI says I have 384 Rows
4. Now from the third worksheet, I want to use a common data point (email address) and have it look through a much larger number of rows, pulling in 2 columns I want to add to my Query. I create a Merged Query (using Left Outer) - great, still have 384 rows.
5. BUT, when I try to expand the created column to pick which columns I want to bring in, it creates a bunch of duplicate rows, now I have over a thousand, many rows of completely duplicate data. I only want it to use my desired 384 rows, just pulling in matching rows with the 2 extra columns of data I want.

What am I doing wrong?

I saw this thread but it is not my issue: https://community.powerbi.com/t5/Desktop/Expanding-columns-after-a-Query-Merge-increases-number-of-rows/m-p/40389#M15168