Have you tried keeping all your web apps and vms in the same resource group, when you do that all the resources withing that group will fall within the same network, and will be able to see each other like they're on the same network.
Have you tried keeping all your web apps and vms in the same resource group, when you do that all the resources withing that group will fall within the same network, and will be able to see each other like they're on the same network.