Foul play was a regular part of pop singles sales back then, most labels - especially those focused on singles like RAK - knew where the chart return shops were and LOADS of singles were hyped in this manner. The Wiki page points out foul play was "suspected" it doesn't come down either way on whether the suspicions had a basis. There are a few cases in which singles were hyped and the labels themselves didn't realize they were sitting on winners capable of charting without help. Friend of a friend stuff so maybe nowt but I did hear a story that one bunch of pluggers were intercepted on their way to hype a single - David Cassidy's The Last Kiss - because it was flying out of shops legitimately and selling well ahead of expectations.
Impressive sales or not nobody's suggesting the new release and its attendant radio play would have put it at #1 in that first week.
Shakin' Stevens kept her off the top with This Ole House which sold well enough to the #5 single over the whole of 1981.
Bangin' tune, mind!