[Gameplay] Indestructible Rek'Sai Tunnel

During a match on Summoner's Rift, my team and I were unable to destroy a tunnel created by Rek'Sai despite standing on top of it. One end of the tunnel was just above the top side river brush, the other end was across the terrain near the blue side top outer turret. All other tunnels were able to be destroyed as normal. Rek'Sai was able to interact with the tunnel normally, even ulting onto it once. This is the first and so far only time I've seen this happen.