Brand spells are invisible

I just did a game on ARAM with an enemy team brand. Brand had previously used all of his spells without any indication of any type of bug. However around the 10:30-10:40 area my team managed to tower dive the enemy team since they were on fairly low health. i watched brand as he cast his ultimate but nothing came out. i immediately thought that it had somehow been cancelled (but on a team with literally 0 immediate cc this was nearly impossible). i then noticed that my allies were taking damage and that the brand ult sound effects were going off on each one. i asked my allies if they saw it, or rather didn't see it, too and they confirmed it. Every ult after that was completely invisible to our team and put us at a great disadvantage because we didn't know who it was going to bounce to and also it hurt our fizz's gameplay because it was impossible to predict. Later on my other teammates started complaining that ALL of his spells were invisible, however for me it was just his ult. I asked the enemy team if they could see the ult and only one member of the enemy team managed to say that she could still see it. I'm not sure if this was just a bizarre bug or a hack (brand never attempted talking to our team despite me requesting what was going on multiple times). I hope this get's on riot's radar and i will also be posting this on reddit for even more awareness.