The Dictionary.ByKeysValues node simply maps the list of values (=keys) with the list of symbols types (in List.Create), and returns as a result a list of symbols instances accordingly to the parameter values from the existing elements (=searchKeys). The parameters syntax in code blocks depends on the parameter type.
When parameters change, to re-run the script should be enough, there’s apparently no need to delete anything (at least that’s what I see).