Frankly, a business needs to ensure that their requirements are met in a cost effective manner.
So, I would start out from the standpoint that your monitoring tools may not necessarily satisfy the business requirements, and that you are happy to work with him to document the monitoring requirements. Once they are documented, show that you can satisfy all the monitoring requirements with a lower cost, and no businessman will decide against you.
Don't fight, cooperate to show that you take the business needs into account, and have actually satisfied them.
If there are any monitoring requirements you don't meet yet ... identify them and let's see if we can provide options, before you have to report.
I can however note that at least two ISPs in South Africa run Hobbit/Xymon (and Devmon). A recent sporting event in South Africa used Hobbit for monitoring components of the network ...
I can give you some more examples off-list.
Regards, Buchan