How to check if an triggered event from MessageId.Server.NewEventsIndication is the same Item as an picked from the ItemPickerForm?

I’ve a list of Items within my Plugin-Item, I want to compare the Items with the BaseEvent object. If I trigger a User-Defined event from the Smart Client, the BaseEvent object is basically empty. None of the fields from that object matches any field with the returned Item from ItemPickerForm..

Saving the list of events(as items):

            using (MemoryStream ms = new MemoryStream())
            {
                var tmpList = new List<string>();
                foreach(var triggerItem in triggerEvents)
                {
                    tmpList.Add(triggerItem.SerializedItem());
                }
                BinaryFormatter bf = new BinaryFormatter();
                bf.Serialize(ms, tmpList);
                ms.Position = 0;
                byte[] buffer = new byte[(int)ms.Length];
                ms.Read(buffer, 0, buffer.Length);
                item.Properties["triggerEvents"] = Convert.ToBase64String(buffer);
            }

I don’t see any variables that add up to anything I can use to compare the 2.

The user-defined event is in .EventHeader.Source

Example of code from a message handler for NewEventsIndication-

var events = message.Data as System.Collections.ObjectModel.Collection<BaseEvent>;
if (events == null) return null;
foreach (BaseEvent ev in events)
{
	// this is the name of the user-defined event that was triggered - ev.EventHeader.Source.Name
}