Hi there, 
I've created a grid with columns that can be added dynamically, but I'm unable to use incell editing in the dynamically created columns. 
QuestionData is a Dictionary<string, object>
Source below: 
<TelerikGrid Data=@QuestionGroup
             ScrollMode="@GridScrollMode.Scrollable"
             Height="35vh"
             EditMode="@GridEditMode.Incell"
             Resizable="true"
             @ref="gridref"
             Reorderable="true"
             RowDraggable="true"
             OnRowDrop="@((GridRowDropEventArgs<EvaluateQuestion> args) => OnRowDropHandler(args))"
             OnCreate="@CreateHandlerAsync">
    <GridSettings>
        <GridRowDraggableSettings DragClueField="@nameof(EvaluateQuestion.Title)"></GridRowDraggableSettings>
    </GridSettings>
    <GridToolBar>
        <GridCommandButton Command="Add">New Question</GridCommandButton>
        <TelerikButton OnClick="NewColumn">New Column</TelerikButton>
        <TelerikButton OnClick="RemoveGrid">Remove Grid</TelerikButton>
    </GridToolBar>
    <GridColumns>
        <GridColumn Field="Title">
        </GridColumn>
        <GridColumn Field="FullQuestion">
        </GridColumn>
        @foreach (string entry in Template.ColumnHeadings)
        {
            <GridColumn Title="@entry">
                <Template>
                    @{
                        var c = context as EvaluateQuestion;
                        if (c.QuestionData.TryGetValue(entry, out var check))
                        {
                            @c.QuestionData.Where(v => v.Key == entry).FirstOrDefault().Value
                        }
                        else
                        {
                            c.QuestionData.Add(entry, new string("test"));
                        }
                    }
                </Template>
                <EditorTemplate>
                </EditorTemplate>
            </GridColumn>
        }
    </GridColumns>
</TelerikGrid>
public void NewColumn() {
        Template.ColumnHeadings.Add(new string("Placeholder"));
        StateHasChanged();
    }
