Your official score from FICO can be calculated in several different ways, using information from any of the 3 bureaus, so there are dozens of different “official” scores. Turbo uses a TransUnion “Vantage score” which is similar to but different from a FICO score and is only based on information from TransUnion. If the other bureaus have different negative information about you (true or not) your score calculated from their information can be lower.
if you are denied credit, I believe the credit bureau must inform you in writing which credit bureau they used. You can get copies of all three official credit reports from www.annualcreditreport.com. Make sure that the reports are accurate and do not have wrong or false information. If a lender has listed an account with the bureau that is incorrect, you can contact the lender and also appeal to the credit bureau.
To actually review your official FICO scores, you would probably have to buy a paid subscription from one of the credit bureaus. They may have a free trial period, but don’t forget to cancel.