Saw this story on UM as well.
As for Gumbley maybe his very name provides one reason for the lack of info. I've seen his last named spelled 5 or 6 different ways in the media and maybe quite simply no one got it right. His first name is spelled either "George" or "Georges" depending on source. Now "Georges" is the usual French spelling for "George", the "s" is silent. Taking into account that this happened in the province of Quebec perhaps Georges/George was a French-Canadian and that "Gumbley" is simply the approximated rendition of a French name on the part of a reporter who didn't know the original spelling.
I'm from Maine and anyone who's ever read a Stephen King novel will have noticed that many of the characters in his stories have French-Canadian surnames. They are very common in New England so I'm a little familiar with them. One common such surname that could sound somewhat like "Gumbley" or "Grumbley" to the unfamiliarized ear would be "Tremblay". Unfortunately if that's the case Temblay happens to be the French Canadian equivalent of Smith and kids named Geroges Tremblay must have been a dime a dozen in Quebec back in the 1950's, making research difficult