Good info provided above, you need to watch him closely, as Virginia Creeper is quite toxic, not so much in the sense that it will kill him unless he ate quite a bit of it, but it does tend to make people/animals that ingest it quite nauseous and sick.
Having a bottle of activated charcoal on hand is a really good idea, I have a bottle in my pet first aid kit/tub, just in case. It's exactly what the animal hospital would do for him if you took him in.
FYI, giving hydrogen peroxide to induce vomiting is an old trick that actually works very well, but apparently isn't recommended for a reptile? I have done this to my dog once per my vet's instructions, and it worked well. I think I gave him a tablespoon of it and waited 10 minutes, and if they don't vomit in 10 minutes you give a second tablespoon and wait another 10 minutes, and if they still don't vomit you give them a third tablespoon and just wait. It typically only takes the first tablespoon with people and dogs. Just out of curiosity because I've never thought about doing this with a beardie, what is the reasoning behind not inducing vomiting in a beardie with hydrogen peroxide?