I don't believe that MySQL tracks a rejection option for an insert ignore. What you can do is pull the number that was successful after the result:
PHP Code:
$iSuccessful += mysql_affected_rows($result);
And initialize $iSuccessful to 0 before the while loop, and you can compare the $iSuccessful to the $counter. $counter should represent the total number of records, while $iSuccessful should indicate the number inserted.
You should consider blocking the query into sets of even 10 entries at a time to save the query counts. Depending on the datasize you could potentially get away with hundreds of entries per query.