[Demon Hunter][Vengeance] PvP talent Jagged spikes not redirecting enough damage

[Xtravagant]

WoW Freakz spell link: https://www.wow-freakz.com/spells.php?spell=205627&&name=jagged-spikes
Bug description: Demon spikes has 100% uptime in the video, and the Shaman has 35% Physical Damage reduction from Armor. As shown in the video, the Shaman does 2,76m damage. Jagged spikes redirects 30% of that which is 828k. The damage should be reduced by 35% which makes the total damage that the Shaman should have taken 538k and he only takes 235k damage.
Proof

[Quicksand]

How much of that is MELEE attack?

Tooltip says:
"While Demon Spikes is active, melee attacks against you cause Physical damage equal to 30% of the damage taken back to the attacker."