New Calendar Event Does Not Display - sharepoint

Question

I'm using C# and CSOM to build an application that creates an event in a SharePoint calendar that I know exists in my O365 subscription. I know O365 is SharePoint 2013, but my application targets SharePoint 2010, so I'm going to have to deal with both versions.
No exceptions are thrown and everything appears to succeed, but the new event does not display in the calendar, even after a page refresh. If I get a collection of items with the same event title, the program-entered event is returned, and appears to contain all the columns set in code.
The CalendarItemCreate function puts data in all the required columns of the calendar. If I search for other calendar items I have hand-entered through the SharePoint calendar, I find them. The only difference I can see between either hand-entered or program-entered events is the "Description" column has ' for the hand-entered events.
Any ideas?
private void CalendarItemCreate(ICalendarItem item) {
using (var context = new ClientContext(_calendarLocation)) {
context.Credentials = _credentials;
var web = context.Web;
var transferScheduleList = web.Lists.GetByTitle(TransferScheduleToken);
var listItemCreationInformation = new ListItemCreationInformation();
var listItem = transferScheduleList.AddItem(listItemCreationInformation);
listItem[TitleToken] = item.EventTitle;
listItem[EventDateToken] = item.EventStartLocal;
listItem[EndDateToken] = item.EventStartLocal.AddMinutes(30);
listItem[DescriptionToken] = string.Empty; //item.EventDescription;
listItem[TransferTypeToken] = item.EventTransferType;
listItem[TransferStatusToken] = item.EventTransferStatus;
listItem[CategoryToken] = "Data Transfer";
listItem[ConfigurationFileLocationToken] = item.ConfigurationFileLocation;
listItem[EventTypeToken] = 0;
listItem[FallDayEventToken] = false;
listItem[FrecurrenceToken] = false;
listItem.Update();
context.ExecuteQuery();
}

Answer 1

The solution was a combination of formatting the dates as strings that SharePoint could understand and data type mismatches in two of my transfer columns. The code below was successful.
using (var context = new ClientContext(_calendarLocation)) {
context.Credentials = _credentials;
var web = context.Web;
var transferScheduleList = web.Lists.GetByTitle(TransferScheduleToken);
var listItemCreationInformation = new ListItemCreationInformation();
var listItem = transferScheduleList.AddItem(listItemCreationInformation);
listItem[TitleToken] = item.EventTitle;
listItem[EventDateToken] = item.EventStartLocal.ToUniversalTime().ToString(#"yyyy-MM-ddTHH:mm:ssZ");
listItem[EndDateToken] = item.EventStartLocal.AddMinutes(30).ToUniversalTime().ToString(#"yyyy-MM-ddTHH:mm:ssZ");
listItem[DescriptionToken] = item.EventDescription;
listItem[TransferTypeToken] = item.EventTransferType.ToString();
listItem[TransferStatusToken] = item.EventTransferStatus.ToString();
listItem[CategoryToken] = "Data Transfer";
listItem[ConfigurationFileLocationToken] = item.ConfigurationFileLocation;
listItem[EventTypeToken] = 0;
listItem[FallDayEventToken] = false;
listItem[FrecurrenceToken] = false;
listItem.Update();
context.ExecuteQuery();