Adding alcohol to bring your mead to 12-15% and then adding more sugar is the principle behind fortified wine like port. The chemical you’re referring to is sulphites, which are produced naturally by yeast anyway.

Clarity depends on a ridiculous number of factors. Adding a bunch of non isomerised alpha acids is definitely going to affect that since isomerised alpha acids cross link with minerals (mostly calcium and magnesium) and proteins, precipitating them out eventually, as well as being important in the creation of foam. In addition, unless you used hop oil for your hop bursting, you added a whole bunch of polyphenols which flip polarity depending on the temperature. Some of these are important in the creation of chill haze, but they’re also important in precipitating out the protein that causes it during the boil. Since you didn’t add bittering hops, that didn’t happen and you’ve likely got a whole bunch of haze causing proteins in there.

On the plus side, it’s just beer. If you enjoy it, drink it. Clarity only really matters if you’re trying to compete in a specific style category and even then, it’s only worth a couple points at best.

I used to do a Capn’ Crunch beer which had toasted coconut in it (side note: I hate that beer, but I made it for my wife’s friends every year at their annual bike party). You want to spread it thin on a cookie sheet and toast at 450F, stirring every couple of minutes or so. Once most of it is brown, you’re good to go. If any of it turns black, stop immediately and discard or it’ll taint your beer with smokiness.