1. Host club didn't want the entries to go away (possibly for a variety of reasons).
2. Suspect engine builder didn't want any of his engines torn down by a potentially biased party.
3. New series is created so that all the folks that were willing to have their engines scrutinized for legality can race against each other and not against people that may be utilizing non-compliant engines.
4. Sole supplier of legal piston knows that he didn't sell pistons to this other engine builder, and the other engine builder must be getting them from somewhere.
5. Other engine builder has been in business for many decades and has a long-standing relationship with multiple parts manufactures. He certainly knows how to build race engines, but is new to the FF world. Builds a few "too fast" motors, ruffles some feathers and raises a few eyebrows.
6. FF long time supporter engine builder believes that custom made, illegal pistons were provided and utilized in these motors with markings identical to those made for him.
7. ...and so it goes...