Is there a of list how to get the skins unlocked???
I don't know if there is a list, but I can tell you how. The zombie skins are done during the Valentine event, that is going on now.
The others are zap skins, some time during the year you'll have the opportunity to zap your HA with the machine that you usually zap your pets with. I believe it'll take Wizard tokens and there's a cool down time of about an hour or a half hour... Uhm, but it randomly changes your HA's skin. I don't remember the exact date for this though.

Ahh ok. thanks. hopefully there is a page that can say where or how to get them
Anything that looks undead/rotting/etc is currently unlockable through the Survival VIP program. The 'Which strain is which' board has a link to SubetaLodge that has gifs of all the viruses stages. The elemental/animal/non-human-in-general is mostly zapper skins we can get during Morostide, which is at the end of October; same as Halloween irl, but lasts longer ;) There's a few that are tied to special site events and/or achievements though. Lace is unlocked randomly when you purchase something at Subeautique. The Flameo skin is part of the Burned achievement, and is unlocked when you get burned by the Red Rreign 100 times during Fireside, which is a holiday that takes place about mid to late November. The Ice skin was a participation prize for the snowman contest that finished up a few days before Survival started, so unless they do another one, I don't think anyone else will be able to unlock that one.
Hope this was helpful :)