EXEC Inside CASE Inside SELECT

I'm trying to execute a stored procedure within the case clause of select statement.
The stored procedure returns a table, and is pretty big and complex, and I don't particularly want to copy the whole thing over to work here. I'm looking for something more elegant.

@val1 and @val2 are passed in


CREATE TABLE #TEMP(
tempid INT IDENTITY (1,1) NOT NULL,
myint INT NOT NULL,
mybool BIT NOT NULL
)

INSERT INTO #TEMP (myint, mybool)
SELECT my_int_from_tbl,
CASE WHEN @val1 IN (SELECT val1 FROM (EXEC dbo.my_stored_procedure my_int_from_tbl, my_param)) THEN 1 ELSE 0
FROM dbo.tbl
WHERE tbl.val2 = @val2


SELECT COUNT(*) FROM #TEMP WHERE mybool = 1


If I have to, I can do a while loop and populate another temp table for every "my_int_from_tbl," but I don't really know the syntax for that.

Any suggestions?