CollisionWorld causing error when readonly in IJobEntity

Unity Engine
, ,
1

Sometimes I get the error below - how should I pass the CollisionWorld to an IJobEntity?
Thank you

InvalidOperationException: BoidSimulation.JobData.ColWorld.EntityBodyIndexMap is not declared [ReadOnly] in a IJobParallelFor job. The container does not support parallel writing. Please use a more suitable container type.

...
...       
var colWorld = SystemAPI.GetSingleton<PhysicsWorldSingleton>().CollisionWorld;
            var job = new BoidSimulation()
            {
                center = ave,
                ColWorld = colWorld,
                boidConfig = boidConfig,
                OtherAgentMoves = AgentMoveLookup
            };
            job.ScheduleParallel();
           
            state.Dependency.Complete();
...
...

[BurstCompile]
    public partial struct BoidSimulation : IJobEntity
    {
        [ReadOnly] public float2 center;
        [ReadOnly] public CollisionWorld ColWorld;
        [ReadOnly] public BoidConfigData boidConfig;
        [ReadOnly] public ComponentLookup<AgentMove2d> OtherAgentMoves;
       
        [BurstCompile]
        void Execute([EntityIndexInQuery] int entityIndexInQuery, Entity entity, ref Boid boid, TransformAspect trans,
            RefRO<AgentMove2d> agentMove)
        {
            var filter = new CollisionFilter() { BelongsTo = ~0u, CollidesWith = ~0u, GroupIndex = 0 };

            NativeArray<DistanceHit> allHits = new NativeArray<DistanceHit>(40, Allocator.Temp);
            var collector =
                new IgnoreSelfAllCollector<DistanceHit>(boidConfig.NeighborRange, ref allHits, false, entity);
            ColWorld.OverlapSphereCustom(trans.WorldPosition, boidConfig.NeighborRange, ref collector, filter);
...
...
2

I seem to isolated it down to an extension method I was using outside of the job in the isystem. I was using a vector2 custom extension method that rotates a vector2. When I use this vector2 exention method, the isystem breaks with the error until I delete the entire .cs file from the plugins folder that contains the extension method.
Would love to learn about why this happens, thank you