I went to re-roll 3 skins, Dark Valkyrie Diana, El Leon Gnar, and Meowkai.. My client crashed as soon as i clicked re-roll for a skin permanent. I opened my client back up and went to the crafting tab and saw that all 3 skins were gone, and there was no permanent skin in their place.. 
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Shoone2 votesHey if you go to the store and check in account settings, you can see what skin you got from your re-roll. I had the same problem a few times and after a bit of digging I found out that it adds the shard to your inventory as soon as it crashes. You're good dude!
Ronoc The Wizard1 votesOh wow thanks dude! Mercenary Katarina XD