Accepting a Virtualized Functions (VNFs) into Corporate IT

Hi, Vendor X wants you to run their VNF (Router, Firewall or Whatever) and they refuse to give you root access, or any means necessary to do 'maintenance' kind of work, whether its applying security updates, or any other similar type of task that is needed for you to integrate the Linux VM into your IT eco-system. Would this be an acceptable offering in today's IT from different type of Enterprises (Minux the Googles, Facebooks...etc) ? Thanks