So I followed your online help to add new camera however it didn't connect. I did use your link that says "If not, try to view your camera from your browser." And of course it immediately brought up the camera with no problems using the credentials I supplied to your camera setup panel. So we know the camera works just fine on port 80 using a standard "http://75.149.181.169" link but apparently your software isn't working with that. If I select other camera under manufacture Vivotek your request for different types of info gets carried away with streams etc. which shouldn't be the case.
So please try and add the Vivotek IB8381-E to your drop down supported camera list.