full join in view

I'm making a report in Crystal Reports, which makes use of full join. As Crystal Reports does not support full join natively, I created a view which contains the join and based my report on that view. The report has also a parameter to filter only subset of rows from view. My problem is, that when selecting from this view, optimizer never uses indexes of neither of two tables.

I understand, that optimizing the filter to the bottom of query tree may not always give the same result with full join (although it should in my case). Alternative could be to use function returning a table, but I doubt I could use this function from Crystal Reports. What other options I have?

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