Hextech Crafting Issue please read

In hextech crafting I got a WWS thresh skin and I decided that I would use the 7 day rental thinking that I would be able to permanently activate it later. I have found out that I will lose the skin shard. I am very annoyed at this and think that you should at least let the user keep the skin shard after the 7 day rental because what is the point in me getting a skin trial if I was just going to lose the skin. I at least think that you should put a warning saying that you wouldn't be able to get the skin back. Please tell me if there is anyway that I can get the skin back because WWS thresh isn't available in the store.