Leo says that's because many webcams broadcast with Flash, and the iPad doesn't support it. So it won't be possible to see those webcams on the iPad.
David discovered that RealPlayer needs an actual installation of Adobe Flash to run, and won't work with the built-in version that's in Chrome.
Leo found a free plugin for Google Chrome specifically made for RealPlayer. He can get detailed instructions here on how to install and enable it.
Leo says using Flash isn't as bad on the desktop as it is on mobile. Leo doesn't like Flash, but Adobe is getting better at keeping it up to date on user's computers. She could even use Flash without even installing it as a separate plug-in by downloading the free Google Chrome at google.com/chrome. The way Chrome handles Flash is much more secure.
Leo says if he's getting a green video signal, that usually is a sign of a bad video card or driver. Disabling Hardware Acceleration may help. Here's an article from Lifehacker on how.
It could also be Flash that's broken. Try reinstalling Flash, or switch to the HTML5 version of YouTube.
Leo says that Adobe makes a flash player for Android if he has Gingerbread OS or later. Go to play.google.com and search for "Adobe Flash Player". They have announced they'll be discontinuing it though, so he should get it while he can.