Help with stuck bonnet please ?

[Podmo69]

Hi all I was wondering if anybody has any ideas on how to unlock the bonnet on a 2007 w221 s class ? I’ve recently had to remove the latches to do some work on the radiator, however after refitting only the drivers side one is working (the easy side , , I’m presuming the passenger side is disconnected,I’ve removed the passenger side wheel arch liner and have tried poking around with a long rod to try to locate the latch and pop it but with visabity poor it’s just not having it , is it possible through the front grill ? Or removing the under trays ?
Any ideas would be much appreciated