On the very first page of the datasheet is noted that the inputs for the AMuxHw MUST be GPIO-pins.
I'm afraid, you'll have to use an AMux or an AMuxSeq which may not be controlled with a signal but must be switched by CPU.
When the frequency is not too high I would suggest to use an interrupt and an Isr-component to switch inputs.
Note there is a new option when starting Creator to get a new tab that looks at analog routing onscreen.
You could use SW controlled muxes and use ISRs off HW triggers, the ISR in turn performs
writes to control SW mux. Some latency to consider.
Looks like I "doubled" with Bobs reccomendations on this, not paying