How many accounts do you have open right now (CCs, loans, mortgages, etc.)?
While it is true not all creditors report to each CR, in the past 10-13 years, I'm sure there was at least one. Bad accounts will only stay on for 7 years and go accounts can stay on for 10 yrs. So, unless you opened these accounts and closed them inside of 3 yrs, you should have something reporting.
I'm thinking you may have a split file. How many accounts do you have listed on EX or EQ?
I'd do a couple things. First, ignore TU's advice. Also, do not ask for the score from TU. Aside of not having one, the score provided by TU is a FAKO score and is worthless to you (and a waste of $$$). The only TU score that matters if a FICO score and that is found here, via myFICO. However, do spend any money for it. The score is calculated based on what is on your CR and nothing is there, so you'd need to get that fixed.
I would consider subscribing to TrueCredit.com (offered by TU). That will show you all three reports, side-by-side, and will allow you to see what is going on. Ignore the provided scores, though and ignore the advice. Anyway, there is a link that says "Dispute", but don't dispute. If you click that, and provide your user name and password, you'll have free pulls for your TU report, rather than paying $10 a pop.
So now you can monitor a lot easier. Answer the questions above, and someone here can follow up.