Here's Bill Cullen's connection to all of this.
Cullen's shows, which may be the earliest ones that GSN has, were from the summer of 1952. There are at least six consecutive shows, going from August 6 (with guest Barry Fitzgerald, possibly the earliest surviving TNTS show) through September 10 (with Eddie Bracken). Meredith Willson returned the next week. Willson probably spent the summer working on a Broadway musical about his Iowa childhood. That would end up working out very well for him.
Cullen made at least one more appearance early in 1953, this time joining Willson on the panel.
As a separate series, Winner Take All had gone off the air in April of 1952. However, it continued as a featured part of a morning show called Matinee in New York throughout the summer, so it was still legitimate to identify Cullen as its host. The last episode of Matinee in New York was on September 5th, so that's why the September 10th episode of TNTS didn't mention Winner Take All.