If Opodo doesn't use Amadeus there is a big chance they use either Sabre or Gallileo.

Here are the links where you can try to pull your intinerary and more important the 6 letter LH reservation code which you then can use to add your booking to LH website.

Amadeus: http://www.checkmytrip.com
Sabre: https://www.virtuallythere.com/new/login.html
Gallileo: http://www.viewtrip.com