So it turns out that even though I am creating a TEMPORARY table wordpress will store those results for a period of time. Therefore doing something as simple as this:
$SQL1 = "CREATE TEMPORARY [...] LIMIT 0, 500";
$SQL2 = "SELECT *, ROUND[...] LIMIT 0, 200";
$wbdb->query($SQL1);
$wbdb->query($SQL2);
Will work.