[BUG] New World Atlas system creates broken PURCHASE_EVENTs without participantId

[Degcube]

Bug Description In 15.9 games (new patch), riot changed that only support players can obtain world atlas. They solved it apparently by giving each support a automatic purchase at timestamp 0:00 in the game. This creates 2 new Events at timestamp 0 in the timeline, 1 for each support. The event data looks like this:

{
  "itemId": 3865,
  "participantId": 0,
  "timestamp": 0,
  "type": "ITEM_PURCHASED"
 },
{
  "itemId": 3865,
  "participantId": 0,
  "timestamp": 0,
  "type": "ITEM_PURCHASED"
 }

As you can see, the participant id is not set.

Expected Result The participant ids for the support players should be set, something like this:

{
  "itemId": 3865,
  "participantId": 5,
  "timestamp": 0,
  "type": "ITEM_PURCHASED"
 },
{
  "itemId": 3865,
  "participantId": 10,
  "timestamp": 0,
  "type": "ITEM_PURCHASED"
 }

Actual Result participantId: 0

Developer Impact Existing systems break, workarounds are possible but not elegant.

Frequency: So far i've seen it in every summoners rift match that has been played after the maintenance was over.

Repro Steps Load the match "EUW1_7385417283" from the MATCH-V5 API. Just the timeline is enough. ParticipantIds are not set in the first frame next to "PAUSE_END".

[GXJackJ]

Seconded.

Easy to solve quickly if you assume the participantIds are in fact 5 and 10, but will fail on minority games where that isn't the case for whatever reason.