AG-Grid footers in tree mode not updating - ag-grid-react

Question

When updating a tree that uses footers in React, none of the footer columns are updating once rendered once.
To render the footer once, I can either start the tree expanded, or expand a row to create the footer row. Once rendered, the values never change even when collapsing and re-expanding the row.
I'm not sure why this behavior is different between the grid modes. After many sleepness nights, my current working theory is that the inferred footer row is not being updated or linked to the original row correctly.
There are a couple of discovered workarounds/clues:
1) deltaRowDataMode=false will work as expected. Because we work with react and immutable stores, I believe we still need this mode to be true.
2) Changing the ID field when doing an update also works as expected. To build a full composite key for our table to detect any change, however, would be very complicated as we can have up to 50 columns as a worst case scenario. The key size would also be huge.
//full plnkr example: https://embed.plnkr.co/Ty1AdL2oQzk9MUqnTHQs/
<AgGridReact
columnDefs={this.state.columnDefs}
rowData={this.state.rowData}
treeData={true}
animateRows={true}
groupDefaultExpanded={this.state.groupDefaultExpanded}
getDataPath={this.state.getDataPath}
autoGroupColumnDef={this.state.autoGroupColumnDef}
onGridReady={this.onGridReady}
groupIncludeFooter={true}
groupIncludeTotalFooter={true}
deltaRowDataMode={true}
getRowNodeId={data => data.id}
groupSuppressAutoColumn={true}
/>
I expect the footer values to change when the total row changes, including the name. Using the first workaround (deltaRowDataMode=false) will show the desired behavior.
Any insight into the cause of the re-rendering issue would be appreciated, or a fix to what I may be doing wrong.

Answer 1

As an alternative, groupRowAggNode can be provided that does update as expected. Still unsure why the original problem exists though.
Example:
https://next.plnkr.co/edit/0zTN0RNzapWbtfTW?preview