Hi Stefan,
That wasn't actual code, just for example, I'll see if I can put together later, however if you look at the examples in the documentation, it's possible to build dynamic items in the suggest event.
https://sapui5.hana.ondemand.com/sdk/#test-resources/sap/ui/commons/demokit/AutoComplete.html#__2
I'm not sure how well this would perform if you are making a oData on input of every key press, so you might need to throttle the number of calls.
Regards,
Jason