For a camera that you add manually using the stream url, you can specify the username and password in the url, so that there is no probe without the correct credentials, e.g.
rtsp://USER:PASSWORD@IPADDRESS/Streaming/Channels/1
For Nest, we can't tell if a device is a thermostat or a camera unless you sign in. For people who do not have Nest cameras, the solution is the same as for anything else incorrectly detected as a camera -- i.e. disable it. However, the last release introduced a bug that prevents the "disable" slider from showing up for the Nest sign-in dialog. This will be fixed in the next release.
Looking at your Hikvision doorbell, I see the one you added manually failing with what looks like username/password problems, or possibly a lockout like before, i.e.: "Server returned 401 Unauthorized (authorization failed)". For the automatically-detected variant, the doorbell is returning "400 (Bad Request)" - perhaps the doorbell does not like the /Streaming/Channels/1 rtsp path that we normally use for Hikvision cameras, or perhaps it's also due to a lockout.
I don't remember for sure, but I think you had said you disabled the automatically-detected variant in the past and the manually-added one was the one that was working. If so, try disabling the auto-detected one and deleting and re-adding the manual one with the username and password in the url.