Semreh is correct about the early A320 Avionic access from the cabin, he is also correct about fluid leakage.
The first time I encountered problems with Kapton wiring was on a very new ( & very early ) A320 when a spilled drink on the carpet above the forward cargo hold leaked into a loom break connector and resulted in a mini fire in the loom that effected multiple systems including opening both the cabin outflow valve, the cabin safety valve and discharging an engine Fire extinguisher.
Go easyI think a little less shouting and a little more listening would be a good idea, just because you have not seen an Avionic bay hatch in the cabin it does not mean it was not fitted to some aircraft, Things change as aircraft evolve and having worked the aircraft from its first delivery into airline service I can tell you a lot has changed over the years.