Power Query SDK - Naming the Output Query

Maybe your code is wrong, or I misunderstood your problem. Here are the code and screenshots.

shared TestRename.Contents = (optional message as text) =>
// START!!!!


    SampleTable();

SampleTable = () => 
    let
        objects = #table(
            {"Name", "Key", "Data", "ItemKind", "ItemName", "IsLeaf"},
            {
                {"JustSomeGuy", "item1", #table({"Column1"}, {{1}}), "Table", "Table", true},
                {"Item2", "item2", #table({"Column1"}, {{2}}), "Table", "Table", true}
            }
        ),
        NavTable = Table.ToNavigationTable(objects, {"Key"}, "Name", "Data", "ItemKind", "ItemName", "IsLeaf")
    in
        NavTable;
Table.ToNavigationTable = (
    table as table,
    keyColumns as list,
    nameColumn as text,
    dataColumn as text,
    itemKindColumn as text,
    itemNameColumn as text,
    isLeafColumn as text
) as table =>
    let
        tableType = Value.Type(table),
        newTableType = Type.AddTableKey(tableType, keyColumns, true) meta [
            NavigationTable.NameColumn = nameColumn,
            NavigationTable.DataColumn = dataColumn,
            NavigationTable.ItemKindColumn = itemKindColumn,
            Preview.DelayColumn = itemNameColumn,
            NavigationTable.IsLeafColumn = isLeafColumn
        ],
        navigationTable = Value.ReplaceType(table, newTableType)
    in
        navigationTable;


// END!!!!!
// Data Source Kind description

After generating the extension and loading it into Power BI and clicking on it in the connector list:

After clicking the OK button：