HUG
I would def go for the referral. If she started to talk etc the stopped, gags easily and wont eat- doesnt sound right.
Have you had a look at her tongue? she isnt tongue tied?
If she sits on your knee at meal times, will she mimic your eating or steal from your plate?
If shes not interested in food I would try to keep her on my knee at meal times, so she can get optimum smells etc and feels included.