Right before you call
this._searchEventsDG.Model.ColWidths.ResizeToFit(GridRangeInfo.Table());
try adding this code:
if(this._searchEventsDG.InvokeRequired())
{
throw new Exception("Wrong Thread");
}
to check whether the call is on the wrong thread.
Are you seeing any other exceptions? These are abount the only thing I can think of that would cause such behavior, a threading problem, or unhandled exceptions that are prventing the standard behavior of the code.