Good Morning,
Not 100% on this but, I think what you may be running into is when you are creating this if I am reading correctly, you are
1. Waiting for a file to be dropped (When a file is created action)
2. It matches the schema of your other Excel files for this folder. So you go to grab it with "List Rows Present in a Table" action
3. Send emails based off a said condition
Your issue is between 1 and 2 so let's look to alleviate that.
Try this first:
I would add a delay of like 30 seconds to start and see if that has any impact, I am assuming it won't.
After this try:
1. Keep this action where you it is. When a file is created (Properties Only) action.
2. Add a small delay just in case 10 to 30 seconds
3. Select the same site collection and library with the "Get Tables" action for the file though put the ID dynamic value from step 1 our trigger.
4. Then from "Get Tables" action perform your row evaluation.
All its really doing is removing you pre-assigning your value you could also go into the ellipses for your action of "Get Tables" and do Settings -> Retry Policy if the delay is hit or miss needed.
If you still need assistance, feel free to follow up. Have a good day!