I apologize for the much delayed response. You are correct, in order to use a custom property to limit a view you would need to have each VM added as a node. VIM actually does not use a node license when pulling a VM into the environment using VIM. VIM will however count each host as a node which gives you the custom property to limit the view on and why it works for your hosts with problems example. Alternatively you can create a view limitation by using the "Group of Virtual Machines" option which allows you to specify what virtual machines you want to include in the view or "Virtual Machine Name Pattern" so you don't have to modify the view each time a specific VM is added (assuming there is a name pattern that will work for you to filter on).
I hope this helps.