[Gameplay & Bugs] Please confirm whether these bugs truly exist

For the sake of publicity this thread is a duplicate from the original thread I wrote on the OCE Board, so here we go.

A few I think are bugs I had ran into during my past few games, I would like to see Riot looking into them to check whether they are actually there or I am mistaken.

1. Renekton will sometimes have sand particle effects around him, showing that he has activated ultimate however that is actually not the case. I have had one game where the player seem to know this and abused that to bait enemies into thinking that he is both low on health and has used ultimate, diving him after the effect wears off only to get killed by his actual ultimate that comes later, making it look like he chained 2 ultimates in a row. Nasus seems to have the same issue as well, my bro ran into the exact same problem on him.

2. When Zilean's ulti is active there would be 3 glowing hourglasses around the target signaling its effect, but when the hourglasses disappear the ultimate isn't actually finished yet. I was killing a Braum who had Zilean ultimate on himself I ran with him until the hourglasses disappeared and killed him with alpha strike (I was playing Yi), only to see him respawn for no apparent reason.

Please look into them.