I don't believe you can use a wildcard with a multiple parameter that way.
Something like this might work
StringVar Array Input := {?AnyStringPrompt}; // replace this with your string prompt
NumberVar howmany:= count (Input);
Numbervar Index;
BooleanVar SelectFormula:= False;
For Index := 1 to howmany do
SelectFormula := SelectFormula OR {DepartmentField} StartsWith Input[Index];
SelectFormula
mlmcc