Treemouth's Festering Splinter slef damage and shield counts as damage done to enemies

[Nandoascal]

Describe the bug
When simming as a tank, Treemouth's Festering Splinter self damage is considered part of your DPS, making it weigh heavily in sims.
However, this is self damage rather than damage to the enemy.

To Reproduce
Have Treemouth's Festering Splinter equipped
Perform a quick sim
Treemouth's Festering Splinter shows up as damage.

Expected behavior
Treemouth's Festering Splinter should not contribute to DPS.
Additionally, it seems to treat the self damage and shield as damage done to enemies.

https://www.raidbots.com/simbot/report/8bxYHkkKhjo3kAeBCS9KWL

Character or /simc input

# Archibaldt - Protection - 2022-12-07 17:09 - US/Stormrage
# SimC Addon 10.0.2-04
# WoW 10.0.2.46924, TOC 100002
# Requires SimulationCraft 1000-01 or newer

warrior="Archibaldt"
level=70
race=kul_tiran
region=us
server=stormrage
role=tank
professions=blacksmithing=60/mining=100
spec=protection

talents=BkEAR5QSZgdnGefDo4ho9ZGXKLgAAAAASSSkkQikSSSaFEBCFJSUSSACkE0CJJICECAAAAAAAkEAAKlGA

# Saved Loadout: Dungeons
# talents=BkEAR5QSZgdnGefDo4ho9ZGXKLgAAAAASSSkkQikSSSaFEBCFJSUSSACkE0CJJICECAAAAAAAkEAAKlGA
# Saved Loadout: Raid
# talents=BkEAR5QSZgdnGefDo4ho9ZGXKLgAAAAASSCJJk0SKJJp0QEiQRIUSSAiIJBtQSCIQIAAAAAAAQSAAoUaA

head=,id=200757,bonus_id=6652/7936/1581/5852/8766
neck=,id=193676,bonus_id=7977/6652/7936/8783/1594/8767
shoulder=,id=192010,bonus_id=6652/1481/5862/8767
back=,id=198959,bonus_id=8978/6652/8815/1488/8766
chest=,id=192006,bonus_id=6652/1472/5864/8766
tabard=,id=165010
wrist=,id=192012,bonus_id=6652/7935/1478/5861/8767
hands=,id=192008,bonus_id=6652/1481/5858/8767
waist=,id=193760,bonus_id=7977/42/7937/8814/1594/8767
legs=,id=192009,bonus_id=6652/1462/5858/8766
feet=,id=200457,bonus_id=1472
finger1=,id=200163,bonus_id=6652/7936/1481/8766
finger2=,id=194082,bonus_id=8837/8838/4785/8780/8802/8792/8850,crafted_stats=36/32
trinket1=,id=200563,bonus_id=6652/1481/5865/8767
trinket2=,id=193652,bonus_id=7977/6652/1594/8767
main_hand=,id=200169,bonus_id=6652/1485/5858/8767
off_hand=,id=190503,bonus_id=8836/8840/8902/8799,crafted_stats=32/36

### Gear from Bags
#
# Hornstrider's Helm of the Feverflare (200)
# head=,id=199001,bonus_id=43/7937/1697
#
# Wyrmforged Helm (363)
# head=,id=192005,bonus_id=6652/7936/1465/5865/8766
#
# Explorer's Expert Spaulders (374)
# shoulder=,id=201952,bonus_id=8851/8852/8799/8850,crafted_stats=49/40
#
# Nokhud Traditionalist's Pauldrons (372)
# shoulder=,id=193686,bonus_id=7977/6652/8813/1594/8767
#
# Isle Trapper's Tunic of the Harmonious (292)
# chest=,id=199014,bonus_id=7968/6652/1714,drop_level=70
#
# Wyrmforged Breastplate (356)
# chest=,id=192006,bonus_id=6652/1478/8766
#
# Stormwind Tabard (1)
# tabard=,id=45574
#
# Wyrmforged Armplates (376)
# wrist=,id=192012,bonus_id=6652/7937/1481/5862/8767
#
# Wyrmforged Armplates (372)
# wrist=,id=192012,bonus_id=6652/7936/1478/5861/8767
#
# Gauntlets of Incalculable Power (372)
# hands=,id=193746,bonus_id=7977/6652/8813/1594/8767
#
# Ravenous Omnivore's Girdle (372)
# waist=,id=193760,bonus_id=7977/6652/7936/8814/1594/8767
#
# Sand-Encrusted Greaves (366)
# legs=,id=200212,bonus_id=43/1625/5858/8766
#
# Wyrmforged Sabatons (363)
# feet=,id=192007,bonus_id=6652/1462/5868/8766
#
# Wyrmforged Sabatons (366)
# feet=,id=192007,bonus_id=6652/1468/5865/8766
#
# Circle of Ascended Frost (346)
# finger1=,id=193731,bonus_id=7978/7975/6652/7937,drop_level=70
#
# Primal Ritual Shell (369)
# trinket1=,id=200563,bonus_id=6652/1472/5864/8766
#
# Gral's Discarded Tooth (356)
# trinket1=,id=192797,bonus_id=6652/1462/5861/8766
#
# Bushwhacker's Compass (372)
# trinket1=,id=198490,bonus_id=6652/1430/5861/8767
#
# Blood of the Khansguard (356)
# trinket1=,id=198627,bonus_id=6652/1414/5861/8766
#
# Ancestral Protector's Stone (372)
# trinket1=,id=197934,bonus_id=6652/1427/5864/8767
#
# Nokuhd Impaling Halberd (372)
# main_hand=,id=192031,bonus_id=40/1478/5861/8767
#
# Earth-Blessed Mace of the Aurora (200)
# main_hand=,id=199045,bonus_id=6652/1704
#
# Dragonbane Lance (376)
# main_hand=,id=200286,bonus_id=6652/1481/5862/8767
#
# Shorebreaker's Poleaxe of the Aurora (200)
# main_hand=,id=199037,bonus_id=6652/1709
#
# Skullsplitting Axe of the Quickblade (200)
# main_hand=,id=199043,bonus_id=6652/1680

# Checksum: b2d710c0

[seriallos]

I've passed this along to SimC developers.