Given what you've posted it's clear that the only thing that should be showing up in your income tax return for the ISO exercise is the adjustment on Form 6251 for the $26,544.
I tried looking through the screens you posted and it didn't help as much as I'd hoped.
The first screen I believe is right at the front end of the TurboTax's overall interview, part of the process I think of TurboTax trying to "customize" the interview for you so that it asks you only about information relevant to your income tax return.
I'm guess the second screen is part of the "ISO Exercise & Hold" interview, though I'm surprised that it simply asks for the correct amount instead of making you enter the Form 3921. In the desktop version there's no opportunity to do that; you're asked if you have a Form 3921 and whether you answer "Yes" or "No" you're presented with the same screen that asks for the Form 3921 information.
I'm guessing that the third screen is somewhere in the "Stocks, Mutual Funds, Bonds, Other" interview somewhere along the ISO "Guide me step by step" interview? Again, surprised that the program simply allows you to enter the needed adjustment; the desktop version solicits the Form 3921 info.
The forth screen seems to be the result of you encountering that page you described in your original post:
"Later, in Other Tax Situations, after selecting :
I exercised ISOs in 2018, but didn't sell the stock in 2018.
I am prompted to add my ISO adjustment amount (I assume the same bargain element as I calculated in Wages & Income?)."
but I was hoping to see the page actually asking the question. And, yes, that number there certainly suggests some "double counting" is going on.
The closest I can come to something like what you're describing in the desktop AMT interview is a page titled "Adjust Investment Income" with boxes for "Gross investment income", "Net gain from disposing of investment property" and "Net capital gain from disposing of investment property", but that screen DIDN'T come up after I filled out the "ISO Exercise & Hold" interview.
But the last screen that clearly is coming off the "Exercise of Stock Options Worksheet", does look correct.
So I'm not sure I can come up with anything conclusive here, though if there's an adjustment on line14 of Form 6251 there's something wrong since you didn't sell any of your ISO shares. You need to get a look at the actual Form 6251 to make the determination, it seems. I'd guess you paid TurboTax their fee? I assume that's how you got the shot of the "Employer Stock Transaction Worksheet"? Yet you don't have a Form 6251 in your income tax return and can't force TurboTax to show it to you?
If the answers to the above questions are all "Yes", then one way around that would be to download the desktop product and the .tax2018 file and look at it there. Let me ask over in the SuperUser's lounge to see if there's an alternative method.
ADDED: according to people who really use online even after you pay you can only look at forms that are included in your income tax return.
