Insert openquery results into an existing table
I will give you an example that has been working for me, it will give you an idea:

DECLARE @Radhe  TABLE(
    [n] [bigint] NOT NULL,
    [Login_Name] [nvarchar](128) NOT NULL,
    [Login_From] [nvarchar](128) NULL,
    [Account_Type] [nvarchar](128) NULL,
    THE_ORDER INT NOT NULL
    PRIMARY KEY CLUSTERED (Login_Name,N)
)



        SELECT @SQL = 'SELECT 
                        [n],
                        [Login_Name],
                        [Login_From],
                        [Account_Type],
                        the_order       
                      FROM OPENQUERY(' + quotename(@SERVER ) + ',' + '''' + 'SET FMTONLY OFF; exec sp_GetServerLogins ' + '''' + ')'

        INSERT INTO @Radhe
        exec ( @sql)