Custom Matrix Visual - Expand/collapse row headers problems

Thanks for timely response,

Having re-read the docs and gone over and made sure I had everything configured correctly, I've gotten no closer.

Here are the selectionIds of rows "Resultat" and "Driftsresultat" respectively from initial post.

{
    "deepestNodeLevelInPath": 0,
    "measures": [],
    "dataMap": {
        "Plan.Lv1": [
            {
                "identityIndex": 14
            }
        ]
    },
    "nodeIsCollapsed": false,
    "nodeIndexes": [
        1
    ],
    "key": "{\"Plan.Lv1\":[{\"identityIndex\":14}]}[]"
},
{
    "deepestNodeLevelInPath": 1,
    "measures": [],
    "dataMap": {
        "Plan.Lv2": [
            {
                "identityIndex": 9
            }
        ]
    },
    "nodeIsCollapsed": false,
    "nodeIndexes": [
        1
    ],
    "key": "{\"Plan.Lv2\":[{\"identityIndex\":9}]}[]"
}

Maybe there's something I missed.