For running J!5.1 you must https://fabrikar.com/forums/index.php?wiki/update-from-github/ or include the new file manually https://fabrikar.com/forums/index.php?threads/joomla-5-1-and-fabrik-cannot-find-files-error.54473/post-285151 See also Announcements
Please see our announcement here.
$formModel->updateFormData('odqeg_fab_voiture___commentaire', '1', true);
$formModel->updateFormData('odqeg_fab_voiture___commentaire', '1', true); // textarea field
$formModel->updateFormData('odqeg_fab_voiture___derniere_attribution', '1', true); // database join field
$formModel->updateFormData( 'jos_fab_ven_atts___venueid', 'Greg' , true );
$jinput = JFactory::getApplication()->input;
$venueid = $jinput->getInt('rowid', 0);
$formModel->updateFormData( 'jos_fab_ven_atts___venueid', $venueid , true );