Not sucking enough during breastfeeding

Liron
I've been seeing a lactation consultant with my baby due to latching issues. Now that she's latching correctly her weight gain has slowed and when we checked how much she was getting during a feeding it was only 1.3 ounces, even though I'm able to pump around 3 ounces at a time normally. The lactation consultant suggested seeing a craniosacral therapist to address possible birth trauma (long labor resulting in c-section) as she noticed my baby seems to hold herself in a tense manner around the shoulders. Anyone have any sort of experience like this? What did you do to resolve it? I see the craniosacral therapist on Sunday.