Receiver Trouble FS-IA6B with Omibus F4 FC

@cleptilectic I think you might have the Rx end of the wiring incorrect (certainly for the more modern i-bus connection protocol). This is for a wizard so the flight controller end might be different - but have a look at this guide How to setup iBUS on Flysky FS-i6 - Georgi Yanev
which should help you get setup in the i-bus serial Rx mode.