Try something like the code below:
function wpse282960_remove_filter() {
$run_import_some_events = run_import_some_events();
remove_filter( 'the_content', array($run_import_some_events->cpt, 'some_events_meta_before_content') );
}
add_action( 'template_redirect', 'wpse282960_remove_filter' );