Will disputing with CRA's first hurt my chances with goodwill later or do I treat the Student Loan Data Furnisher (EdFiniancial) like any other credit dispute?

I'm guessing these are federal student loans. If this is the case, the normal means of credit repair fly out the window. Federal Student Loans are required, by law, to report on your CR 100% accurately. Any late payments are there for 7 years. Student loans are next to impossible to get off your CR, too.

If these are private student loans, the rules are a little more flexible and you should try goodwill first.

I think I'd try a well-crafted goodwill attempt first.