Is there potion for experiment # 911?

Not specific for that experiment. There might be a direct option with the Miracle Potion II, it says it can change your pet into any species, but I keep forgetting if that includes experiments or not, and I can only seem to find really old threads for them, so I hope someone can come here and clarify further.

Random experiment options: Experimental Dew Changes pet into a random Experiment pet.

Pet Zapper If you check the box (in the blue box)! Wait, what’s that - you’re just here for the Experiments? Well my friend, I am all for your voyage of volatile variety! But my Experiments are rather special, you see. I require a very necessary fee to set my Zapper to ‘Experiments only’. It helps me develop future Experiments! For an additional 400,000sP you can ensure that your zap will be a random experiment. Now isn’t that fair? Pay 400,000 sP and 15 wizard tokens for a guaranteed (but random!) experiment.

Thanks for confirming, I hope I can remember this time. :P

So yes, a Miracle Potion II can change your pet directly into the experiment that you want. It's for sale in the Cash Shop at 1k CSC.

Thanks