Sankey: Adding more data to hovertemplate (tooltip). Is custom data the answer?

Hopefully you can see that Iā€™m trying add the mean, median, and number of units into the tooltip from a pandas data frame. Obviously I can have two through using values and custom data, but I was wondering if there was a way to increase the amount of data/information in the tooltip as per the below function:

def genSankey(df,cat_cols=[],value_cols='',title='Sankey Diagram'):
    # maximum of 6 value cols -> 6 colors
    colorPalette = ['#FFD43B','#646464','#4B8BBE','#306998']
    labelList = []
    colorNumList = []
    for catCol in cat_cols:
        labelListTemp =  list(set(df[catCol].values))
        colorNumList.append(len(labelListTemp))
        labelList = labelList + labelListTemp
        
    # remove duplicates from labelList
    labelList = list(dict.fromkeys(labelList))
    
    # define colors based on number of levels
    colorList = []
    for idx, colorNum in enumerate(colorNumList):
        colorList = colorList + [colorPalette[idx]]*colorNum
        
    # transform df into a source-target pair
    for i in range(len(cat_cols)-1):
        if i==0:
            sourceTargetDf = df[[cat_cols[i],cat_cols[i+1],value_cols[i],value_cols[i+1]]]
            sourceTargetDf.columns = ['source','target','avglaghrs','coils']
        else:
            tempDf = df[[cat_cols[i],cat_cols[i+1],value_cols[i],value_cols[i+1]]]
            tempDf.columns = ['source','target','avglaghrs','coils']
            sourceTargetDf = pd.concat([sourceTargetDf,tempDf])
        sourceTargetDf = sourceTargetDf.groupby(['source','target']).agg({'avglaghrs':['mean','median'],'coils':'nunique'}).reset_index()
        
    # add index for source-target pair
    sourceTargetDf['sourceID'] = sourceTargetDf['source'].apply(lambda x: labelList.index(x))
    sourceTargetDf['targetID'] = sourceTargetDf['target'].apply(lambda x: labelList.index(x))
        
    # creating the sankey diagram
    data = dict(
        type='sankey',
        valueformat = ".2f",
        valuesuffix = "Hrs",
        node = dict(
          pad = 15,
          thickness = 20,
          line = dict(
            color = "black",
            width = 0.5
          ),
          label = labelList,
          color = colorList
        ),
        link = dict(
          source = sourceTargetDf['sourceID'],
          target = sourceTargetDf['targetID'],
          value = sourceTargetDf['avglaghrs']['mean'],
          customdata = sourceTargetDf['coils']['nunique'],
          hovertemplate = '%{customdata} coil(s) spent %{value} on<br />'+
                            'average to get from %{source.label}<br />'+
                            'to %{target.label}. %{median}<br />'+
                            'was the middle value.<extra></extra>'
        )
      )
    
    layout =  dict(
        title = title,
        font = dict(
          size = 10
        )
    )
       
    fig = dict(data=[data], layout=layout)
    return fig

Thanks.