Unfortuntely, the totalthreads and totalposts variable has been formatted by the time you get to the forumhome_complete hook, so you would have to actually edit these lines to add it in in the forum.php file:
PHP Code:
$totalthreads = vb_number_format($totalthreads);
$totalposts = vb_number_format($totalposts);
Something like adding this right above:
PHP Code:
$totalthreads = $totalthreads + 60000;
$totalposts = $totalposts + 700000;
If you show those stats elsewhere, then you will need to modify the code there too.