childhood memories

DICK TRACY RETURNS was one of my earliest memories of going to the movies in Mount Rainier, Md., and for years I swore that I had seen all but one chapter. I could remember bits and pieces(Tracy, Mike and Steven in the mine with a timebomb ticking away, Middleton's death scene, etc.) But I could never find out Tracy exchanged certain death from the dynamite planted in the hillside.
I finally saw the entire serial in 1981 and was amazed at how many chapters I had missed.
Points of curiosity: Is it coincidence that Dave Sharpe's character is named "Ron Merton" and Champ Stark is played by John Merton? And if Ron Merton made such an indelible impression on Tracy in this serial, why doesn't he recognize him in DICK TRACY VS. CRIME INC?