Well, you are right, Sleep talking occurs (most commonly) during NREM periods. But really, sleep talking is harmless. It is normally quiet, and goes away in not too long.

If it is loud or angry, then it is usually in association with another sleep disorder, in which case, it is probably brought on or exacerbated by stress.

Don't worry so much about LDing, and if it is quiet, just wait it out.

Take it easy, and happy lucids.