I must admit this series confuses me. In this particular issue, the words "THE INVISIBLE" appear to have been re-lettered over some previously-existing name in the captions and balloons (apparently there wasn't enough space to re-letter the words "The Invisible AVENGER"). And in the subsequent issues scanned and available here, we have Blue Ghost and Cometman -- no character called Invisible Avenger (or even just "The Invisible") appears anywhere in those issues.
Link to the book:
Invisible Avenger 11