The clinic we are going through to see the paed will refer straight to RCH if they think there is an issue so that's good.
I'm in Adelaide so haven't obviously gone through RCH but from all the reports from Victorian members they are awesome and will take excellent care of your DS if needed so great that you have access to their services

Yeah the internet can cause more worries, rather than provide the simple info you need so you really need to read everything with a grain of salt. I had myself convinced that my DS would need surgery or worse . His case is moderate and our treatment is a dennis brown brace for 6 months (we are 4 months in), but in the early days it was just devastating.

Hopefully the time until your appt will go quick, waiting can do your head in

ETA - not sure if hypermobility and hip dysplaysia are the same thing, I've never had hypermobility mentioned to me from our specialists, sorry