NullReferenceException in IncidentWorker_RoadWorks.RandomNearbyTradeableSettlement

[mewtopian]

There was a nearby "pristine ruins" from Real Ruins, but I don't know if that was related.
I checked my IncidentWorker_RoadWorks file and it looks the same as the current master.

System.NullReferenceException: Object reference not set to an instance of an object
  at MoreFactionInteraction.IncidentWorker_RoadWorks+<>c__DisplayClass5_0.<RandomNearbyTradeableSettlement>b__0 (RimWorld.Planet.SettlementBase settlement) [0x00000] in <filename unknown>:0 
  at System.Linq.Enumerable+<CreateWhereIterator>c__Iterator1D`1[RimWorld.Planet.SettlementBase].MoveNext () [0x00000] in <filename unknown>:0 
  at System.Collections.Generic.List`1[RimWorld.Planet.SettlementBase].AddEnumerable (IEnumerable`1 enumerable) [0x00000] in <filename unknown>:0 
  at System.Collections.Generic.List`1[RimWorld.Planet.SettlementBase]..ctor (IEnumerable`1 collection) [0x00000] in <filename unknown>:0 
  at System.Linq.Enumerable.ToList[SettlementBase] (IEnumerable`1 source) [0x00000] in <filename unknown>:0 
  at Verse.GenCollection.TryRandomElement[SettlementBase] (IEnumerable`1 source, RimWorld.Planet.SettlementBase& result) [0x00000] in <filename unknown>:0 
  at Verse.GenCollection.RandomElementWithFallback[SettlementBase] (IEnumerable`1 source, RimWorld.Planet.SettlementBase fallback) [0x00000] in <filename unknown>:0 
  at MoreFactionInteraction.IncidentWorker_RoadWorks.RandomNearbyTradeableSettlement (Int32 originTile) [0x00000] in <filename unknown>:0 
  at MoreFactionInteraction.IncidentWorker_RoadWorks.CanFireNowSub (RimWorld.IncidentParms parms) [0x00000] in <filename unknown>:0 
  at RimWorld.IncidentWorker.CanFireNow (RimWorld.IncidentParms parms, Boolean forced) [0x00000] in <filename unknown>:0 
  at RimWorld.StorytellerComp+<UsableIncidentsInCategory>c__AnonStorey3.<>m__0 (RimWorld.IncidentDef x) [0x00000] in <filename unknown>:0 
  at System.Linq.Enumerable+<CreateWhereIterator>c__Iterator1D`1[RimWorld.IncidentDef].MoveNext () [0x00000] in <filename unknown>:0 
  at Verse.GenCollection.TryRandomElementByWeight[IncidentDef] (IEnumerable`1 source, System.Func`2 weightSelector, RimWorld.IncidentDef& result) [0x00000] in <filename unknown>:0 
  at RimWorld.StorytellerComp_CategoryMTB+<MakeIntervalIncidents>c__Iterator0.MoveNext () [0x00000] in <filename unknown>:0 
  at RimWorld.Storyteller+<MakeIncidentsForInterval>c__Iterator1.MoveNext () [0x00000] in <filename unknown>:0 
  at RimWorld.Storyteller+<MakeIncidentsForInterval>c__Iterator0.MoveNext () [0x00000] in <filename unknown>:0 
  at RimWorld.Storyteller.StorytellerTick () [0x00000] in <filename unknown>:0 
  at Verse.TickManager.DoSingleTick () [0x00000] in <filename unknown>:0