How can I observe dynamically generated UI from data table cell click?

Question

To edit a one-to-many like data structure,

1. I would like to create a data table (DTOutput), on which I observe cell clicks observeEvent(input$groupingsOut_cell_clicked, {...}).
2. Then at every cell click, I would like to generate input fields on the UI.
3. Finally, I would like to listen to changed on those rendered/generated UI.

I can't edit these cells directly in the DTOutput, as it doesn't support vectors within cells. (Hence, one-to-many relationship).

I have managed steps 1 and 2. I can render a DTOutput with corresponding cells. I can observe cell clicks and insert UI (insertUI()) upon cell clicks. I created observeEvent objects to observe those rendered fields. However, those observeEvents are never fired upon editing newly generated fields.

ui = fluidPage(title = titlePanel("Title"), 
               tags$head(tags$style(HTML("hr {border-top: 1px solid #000000;}"))),
               sidebarLayout(
                sidebarPanel(),
                mainPanel(tabsetPanel(type = "tabs",
                                      tabPanel("Groupings", DTOutput(outputId = "groupingsOut"), 
                                             tags$div(id = 'placeholder')),
                                      tabPanel("Test", textOutput(outputId = "statusOut")),
                                      tabPanel("Plot Generator", plotOutput(outputId = "distPlotOut")))
                )
               )

)
server = function(input, output) {
    # Label reactive values
    labelRVs = list()

    #Example table
    groupings = data.frame(names = c("cars", "mbikes", "bikes"), 
                           labels = c("Cars", "Motor Bikes", "Bikes"),
                           groups = I(list(c("toyota", "vw", "tesla"), c("harley", "kawasaki"), c("somth", "anoth", "bla"))),
                           groupLabels = I(list(c("Toyota", "VW", "Tesla"), c("Harley Davidson", "Kawasaki"), c("Something", "Another Thing", "Bla bla"))))

    #groupings = data.frame()

    proxy = dataTableProxy('groupingsOut')


    observeEvent(input$groupingsOut_cell_clicked, {
        info = input$groupingsOut_cell_clicked
        if(!is.null(info$row)){
            grouping = groupings[[info$row, 1]]
            groupingLabel = groupings[[info$row, 2]]
            groups = groupings[[info$row, 3]]
            groupLabels = groupings[[info$row, 4]]

            # remove previously generated UI
            removeUI(selector = paste0('#placeholder input'), multiple = TRUE)
            removeUI(selector = paste0('#placeholder label'), multiple = TRUE)

            # Generating ID for grouping labels
            id = paste0("groupLabel_", i)

            # Inserting text input for grouping label
            insertUI(selector = '#placeholder', ui = textInput(id, label = "Grouping label:", value = groupingLabel))
            labelRVs[[id]] <<- observeEvent(id, {
                cat(paste(id, i, "\n")) # THIS LINE ONLY RUNS AT INITIALIZATION :(
                })

            lapply(1:length(groups), function(i){
                index = sprintf("%03d", i)
                id = paste0('label_', index)
                insertUI(selector = '#placeholder', 
                         ui = textInput(id, label = paste0("Group label for ", groups[i], ":"), value = groupLabels[i]))
                labelRVs[[id]] <<- observeEvent(id, {
                    cat(paste(id, i, "\n")) # ALSO THIS LINE ONLY RUNS AT INITIALIZATION :(
                })
            })
        }
    })

    output$groupingsOut = renderDT(groupings[, c(1, 3)], rownames = FALSE, editable = TRUE, selection = 'single')

}
shinyApp(ui = ui, server = server)

However, this example Shiny - Can dynamically generated buttons act as trigger for an event runs perfectly fine. In the example instead of insertUI into tags, renderUI to outputUI is used. I adapted my code above to use renderUI, which also failed. At this point, I am suspecting if DTOutput doesn't behave the same way as other input fields.

Beaware of the usage of <<- operator to assign labelRVs to keep observeEvent objects alive. This is indeed necessary, which is shown in the example.

I wonder, if there is any way to observe such fields?