Joining a MultiLookup on a multi-value report parameter

I can't seem to figure out what's wrong with this multi-lookup syntax on a textbox expression:

=Join(MultiLookup(Split(Parameters!LineType.Value,","), Fields!Message.Value, Fields!Translation.Value, "dsGetTranslations"), ",")

LineType is a multi-value, hidden, text report parameter with no available values specified, and default values from another dataset.

I'm receiving this error: "The value expression for the textrun 'txtHeader.Paragraphs[0].TextRuns[0]' contains an error: Conversion from type 'Object()' to type 'String' is not valid.

This expression works OK if I just look at the first LineType element alone:

=Lookup(Parameters!LineType.Value(0), Fields!Message.Value, Fields!Translation.Value, "dsGetTranslations")
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Arifhusen AnsariBusiness Intelligence Developer and AnalystCommented:
Try this.

Join(MultiLookup(Split(join(Parameters!LineType.Value,","),","), Fields!Message.Value, Fields!Translation.Value, "dsGetTranslations"), ",")

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jdallen75Author Commented:
Fantastic - it would have taken me a while to figure out 2 Join's. Thanks!
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