Apple

Loctite recommend for removing superglue from (specifically) plastic:

"Getting glue off plastic is straightforward. Soak a cloth in vegetable oil or skin moisturiser and rub it against the glue. Wait for the substance to soak in, and then clean the surface. White vinegar also works well: soak the area in vinegar, then remove the glue with a dull edge such as a spatula."

If I was in your situation, I'd mainly be concerned about gunking up your keyboard by getting further stuff underneath/around the keys, or worse, liquid making its way to the electronics underneath.

So, while I can't recommend it because I haven't tried it, what I'd do is bung tissue paper between the gaps around the key, ready to soak up any excess liquid. Then carefully put a drop of vinegar onto the superglue, let it sit for a minute, and try scraping the glue off with a fingernail. I don't have a pipette, but I'd be worried about trying to extract one drop carefully from an entire bottle, so I'd pour some into a bowl first, then dip something into it to transfer a drop.

try using a small amount of goo gone. It's just citrus oils pretty much and is fairly effective in removing adhesives, I used it on uniforms in the past to remove patches, it doesn't discolor or corrode anything.

If it is only on the keycap (and has not gone into the keyboard mechanism), my recommendation would be to let it dry. You can always get a replacement keycap off amazon or ebay. A trip to the Apple store may even get you one for free - if they happen to have a dead macbook hanging around out the back.