Ev Ult into Vi ult???

http://na.op.gg/summoner/userName=LaytoSlayz this is my op.gg, Vi is amazing, I can't believe how strong she is. Anywho, Vi ult is unstoppable "Active: Vi dashes **unstoppable **to the target enemy champion, upon arrival deals physical damage and  knocks them up for 1.25 seconds. Enemies along the way are  knocked aside and dealt 75% damage." BUT (on more than one occasion), I have ult'd the new evelynn and she will ult, and it doesn't disconnect the chain but it wont knock her up or do any damage... Is this a bug???

TL;DR, I'm Confused [zombie-brand-mindblown] Thanks! <3 [slayer-jinx-catface]