The only way I thought of is definately a ugly workaround. I usualy pass multi values parameters to reports, not use them in the report itself.

You could pass your MV parameter to a db Stored Proc as a string using =Join(@ParamName.Value,",")

Then in the SP split the values into a result set and return that.

you'd start with "value1,value2,Value3"

and get as a dataset

Value1

Value2

Value3

Then use those values to control your Visibility.