Dear Denise,
Have you thought about a referal to a oral/speech specialist?  Is there
someone in your area?  Did you give the supplemental system 2 weeks?
I have sent some of my babies to a oral/speech specialist when I have a baby
problem related to the suck.  They look at the picture at a slightly
different approach and the oral/mouth area is their strength.  Concidering
the importance of this isssue you could probably push for an urgent status
for this referal.  Good luck.
Ann Perry RN IBCLC