Karthus Q Casting

Hi, I have recently picked up Karthus and really enjoy playing him. However, I've noticed a major problem in the mechanical design of the character that is throwing off my gameplay. I am used to Quick Cast with Indicator (a toggleable option under hotkeys), and have it assigned to every ability on every character. However, Karthus is unique. For some reason, Karthus's Q (Lay Waste) refuses to obey this type of casting, and instead is set and unchangeable on normal Quick Cast. This means that Quick Cast and Quick Cast with Indicator both produce the same results with Karthus's Q, and both act the same as Quick Cast. I have already created a ticket and discussed this with two Riot employees, the first saying he doesn't know and deferring me to the second, who also said they don't know and have no way to get this complaint to Riot officials. The second employee I talked to suggested I post this complaint here, and claimed it is the most likely place to get fixed. Is there any plans for this to be fixed in the future? I was told that Cassiopeia's Q used to be the exact same and was fixed, so why wasn't Karthus's? Thank you for any help, I hope this will be addressed soon, as I really like this champion but this unchangeable Quick Cast setting is really hindering my enjoyment.