I would suggest bringing a recording device or other transcription device. Take liberal notes if you can; also note where they seem to deliberately make taking notes difficult. For now, don't pay too much attention to discrepancies--it will be impossible to take accurate notes if you do. But you should mark them inconspicuously at this time. Try to write what they are saying, or get a transcription of what they are actually saying.
After you get home, now is the time to tear apart the notes. Now, do the research on how they are making it difficult to take notes, and what they are doing that is not in the Bible. Pay key attention to what goes on Sunday afternoon, with the "a generation" talk, and how they try to present it. Also, pay attention to anything about disfellowshipped family or unbelieving relatives--they are trying to drive families apart. And once you finish dissecting it, then post what you heard here on this site.
Also, pay particular attention to the new Kingdumb maladies. Observe what you see. Are they singing them correctly? Do people seem to be enjoying them? Or, are they dogging singing them, hating them, grumbling about them, or singing way off key? Or, are the songs so poorly written (and the accompaniment so poorly performed) that singing them right is impossible?