Use the following code to change a View's order when a specific URL parameter and value are set. Replace 123 with the ID of your View, replace my_param with your parameter name, replace custom_value with your specific parameter value, and replace 150 with the ID of the field you want to order by.

add_filter( 'frm_filter_view', 'change_my_view_object', 10, 1);
function change_my_view_object( $view ) {
	if ( $view->ID === 123 ) {
		if ( isset( $_GET['my_param'] ) && $_GET['my_param'] == 'custom_value' ) {
			$view->frm_order_by = array( 150 );
			$view->frm_order = array( 'DESC' );
		}
	}

	return $view;
}