RadzenAutoComplete nullable properties when filtering

I use an RadzenAutoComplete within a custom FilterTemplate. When a property in de Data has a NULL value the RadzenAutoComplete will crash because it cannot handle NULL values.
This is solvable by checking if the properties is NULL and give it a string.Empty value, but having to always set values to properties that are actually NULL isn't a proper solution.

So this makes my question; is it possible to make the RadzenAutoComplete ignore the NULL values?