Can't help on the trampoline.
IIRC, the concerns with DD2 relate to ASD? If so, this is my experience... If not, the following may be no help.
I know exactly what you mean - we 'entered' the system in Oct and don't seem to be getting far! It;s rotten. I have found the following, which may or may not help.
The education system moved faster for me than the health system - we've seen an Ed Psych who was fairly helpful. Can the preschool refer to EP? Does DD2 get any extra assistance at preschool?
Also I insisted on a separate SALT referal in addition to the CDC referal, and an initial SALT appt has come through already, while the CDC isn't due till April. Can you try that?
I find it helps my sanity if I know when appts are likely to come up. Call the CDC, ask to confirm that they have received the referal and ask if they can advise roughly when you'll hear about the appt and when it's likely to be. Round here the responses are typically something like "we send out the next bunch of appts in March for the following two months" or "there's currently a 6mo waiting time between referal and appt". I find it helps me just to know how long.
We have a local "opportunity group" who have various drop-in, specialist and nursery / preschool sessions including SALT. They were frinedly, helpful and welcoming. Do you have anything like this?
I find that so far, I have to scratch together tips and info from any professional I come across, rather than having specific input for me.
Probably no use at all, but is there a local toy library who could rent you a trampoline?