Rodney definitely took major influence from Timbaland when he started working with MJ. Just listen to this song he produced for Brandy on her 2002 Full Moon album:
Sounds a lot like "Heartbreaker", and by extension, Timbaland productions like "Pony", "Are You That Somebody", "None of Your Friends' Business", etc. Those songs aren't dubstep; as someone else said, they're R&B and hip-hop songs with significant drums 'n bass influence. Dubstep evolved from drums 'n bass, but MJ was nowhere near the first major artist to have elements of drums 'n bass in his music.
And even if "Heartbreaker" somehow was dubstep, why give MJ credit for that? If anything, it would just be Rodney's accomplishment as he produced the song; MJ had little input on it as with many songs on the album.