Now regarding its opposite, "The Newlywed Game", April/May 1969 happened to be the oldest primetime episodes being rerun but the oldest daytime episode they reran was "72-006" which could well be January 11, 1972. Now, unlike The Dating Game, NG episodes from the ABC run hasn't been reran prior to the Y2Play Marathon they had. But again, it's very difficult to pinpoint the exact air dates of many episodes of the original NG.
Actually, GSN did air a few daytime episodes from 1969. In their old "Game Show Saturday Night", the first time they featured
Newlywed Game they aired 8 episodes from 1969. The first was a primetime show from May 3, 1969 (I know the date because Bob mentions it was Kentucky Derby day, and old TVGuides show that as 5/3/69). The other episodes they ran were from '69 daytime - oddly enough, one of them already existed in the trade curcuit from a B&W kinescope w/o/c.
They also aired a bunch of '72 episodes, including a couple from late April '72 (I think Bob mentions something about Easter being last week - I'd have to go back and re-watch the two I have to make sure). So it is possible to pinpoint airdates of some of them.