Karthus W doesn't proc phase rush?

So there's a guy on the Karthus mains Discord server who's been testing the new runes on Karthus and I asked about Phase rush, which states that hitting an enemy with 3 seperate attacks or abilities give %30-60 movespeed based on level, but after checking he said that it didn't work on Karthus's W. Isn't walking into the W technically considered being hit with the ability?

Just checking if this really is working as intended or if Karthus's W is one of those weird cases or something :P