If your planned route takes you near CTA, or if you are unfamiliar and not entirely sure - just give the relevant freq a call and let them know you are there.
A couple of locals around here regularly call up (no FPL) just say where they are, where they are going and what level. We can then assign a code or even just use "squawk ident" to identify them and either give them a clearance or reassure them that their planned track/alt will keep them clear of CTA and call again if they need higher or diversions left/right of track. Takes a minute of your time and helps with our air picture (traffic OCTA for acft leaving etc)
We're here to provide a service. If clearance through CTA is not available, there has to be a bloody good reason for it, we're not allowed to just pick and choose who gets in and who doesn't it. Like I said at the start of this thread - we are all on the same team - you need to get somewhere - I want to ensure you and everyone else in the sky gets there safely and as expeditiously as possible.
There is no need to "run and hide". Jokes aside, never turn your transponder off, it's insane to think you would rather risk conflicting with someone than get a letter from CASA!