Nope, doesn't work. The only way TurboTax allows ANY mortgage interest deduction is if I answer "No" to your step 21. I originally answered Yes and used the actual home acquisition date (in 2005), but went through your steps and used the Box 3 date instead (date of refinance in August 2017). Same result - zero allowance for mortgage interest.
If it works for you on a typical (smaller) loan, I suspect you have a bug related to the automatic calculation of allowable interest for loans >$1M. When I answer No in step 21 (and everything else is the same), the exact right amount is allowed (which is less than the total interest paid) for my itemized deductions. This is a very expensive error for TurboTax customers.
