In my case : i want to reload the ag grid with user selected (when user navigate back using previous button ).

Below code will reselect the checkbox again, based on userContext name value.

Code:

const gridReady = (params) => {
     params.api.forEachNode((node) => {
      if(node.data.name === userContext.name) {
        node.setSelected(true); 
      } 
    });
}

<AgGridReact onGridReady = {gridReady}/>