when applying filter on group-headers in ui-grid , they disappear . i have the same problem with column-footer when we have it in result of a grouping operation (when footer aggregate function is defined without grouping it is shown correctly with applied filter ).
col.cellTemplate='<div>{{COL_FIELD | currency:"":0}} </div>';
i have to change it to bellow to get it work:
col.cellTemplate=
'<div ng-if="!row.groupHeader">{{COL_FIELD | currency:"":0}} </div>'
+'<div ng-if="row.groupHeader" >{{COL_FIELD }}</div>'
but it is not what i really need ;