The "bonus roll ID" or "eligibility" so to say as well as the weekly loot is tracked (as always with world bosses) via 2 quests. You can check your eligibility with the following script:
/script for k,v in pairs({["Sotanathor killed this week"]=49171,["Sotanathor Bonus Roll used"]=49177})do print(format("%s: %s", k, IsQuestFlaggedCompleted(v) and "\124cff00ff00Yes\124r" or "\124cffff0000No\124r")) end
WoW Zone
Greater Invasion Point: Sotanathor
Shadowlands - Level 45-45.
Details
Counts are what the current game build's data holds for this zone.
Map

The in-game map of Greater Invasion Point: Sotanathor.
Community notes from Wowhead · 2 comments
The comments below were written by Wowhead users. They are community notes, not TheWoWDB comments. See them in context on Wowhead.
Greater Invasion Point: Sotanathor
You need to kill [npc=124555] He have over 1500M HP O_o. take me 8 min to kill him O_o ( low number of group ).
See My Video if need it - Greater Invasion Point: Sotanathor Video
Quests the game data places in this zone. Open one for its objectives and rewards.
Quest Rewards in Greater Invasion Point: Sotanathor
Blizzard's quest data places 1 quest in Greater Invasion Point: Sotanathor. Together it awards 6,150 experience and 20g 22s in coin. It is open to characters of level 45.
Totals are summed from the Blizzard game data API quest records for this area; a quest that offers a choice counts every option once.