BWF files are only practical if all the collaborators agree in advance to use them, and everybody works from a common template with exactly the same run time and tempo. Otherwise, they can be more trouble than they're worth. Most folks just export vanilla wave files and export them from 00:00 so they're easy to line up in the master project.
I'm assuming "doesn't sound right" means your track is not synchronizing properly with the master project. If you're consistently exporting from 00:00, then it's possible your project's tempo doesn't exactly match theirs. Verify the BPM and (if using MIDI to drive external synths) PPQN values of the project you're contributing to, and make sure they don't have any tempo changes in it. You might even request an empty copy of the master project file just to make sure.