Does the wreq database differ from the req database?
IIRC wreq was a fork in the req developement, so it may not differ too much.
There were scripts to import a req database into RTv1 so, in theory, you could (tediously) import your wreq database into a req database, import that into RT1, then import that into RT2, and then import that into RT3.
It would probably be faster to just write a script to do the import directly though.