[TYPO3-mvc] Specific typoscripts not used in eID script

[Philipp]

Hey!

In my extension i needed to overload the Typo3DbBackend Class, to link it and make use of it i wrote this piece of typoscript and included in in my ext_typoscript_setup.txt

config.tx_extbase.objects.TYPO3\CMS\Extbase\Persistence\Generic\Storage\BackendInterface.className = Vendor\Extension\Persistence\Generic\Storage\PatchedTypo3DbBackend

This works well for me

But in an eID script i wrote it is not used.

I boot my frontend environment like this:
$GLOBALS['TSFE'] = Utility::makeInstance('TYPO3\\CMS\\Frontend\\Controller\\TypoScriptFrontendController',$TYPO3_CONF_VARS,$id,0);
	/* @var $GLOBALS['TSFE'] Frontend\Controller\TypoScriptFrontendController */
	$GLOBALS['TSFE']->connectToDB();
	$GLOBALS['TSFE']->includeTCA();
	$GLOBALS['TSFE']->initFEuser();
	$GLOBALS['TSFE']->checkAlternativeIdMethods();
	$GLOBALS['TSFE']->clear_preview();
	$GLOBALS['TSFE']->determineId();
	$GLOBALS['TSFE']->initTemplate();
	$GLOBALS['TSFE']->getConfigArray();
	$GLOBALS['TSFE']->newCObj();
	Frontend\Utility\EidUtility::connectDB();

	$objectManager = Utility::makeInstance('TYPO3\\CMS\\Extbase\\Object\\ObjectManager');
	/* @var $objectManager \TYPO3\CMS\Extbase\Object\ObjectManager */

...

some parts of the typoscript work, like the persistence settings

how can i make use of my patched database backend in the eid service?