The first picture you posted is Bea Benaderet, who was Kate Bradley on Petticoat Junction and Blanche Morton on Burns and Allen.
You are correct. It doesn't look at all like June Foray.
Interesting bit of confusion on the part of the poster of that picture: Bea Benaderet did do the voice of Betty Rubble from 1960-1964. June Foray did Betty in the 1959 pilot.
Bea Benaderet didn't voice Warner Brothers Granny though - that was June Foray.
So the author of that website where I grabbed the shot has a bit of 'splainin' to do...LOL
And also (cousin) Pearl, Jethro’s mom, on the Beverly Hillbillies.
When producer and writer Paul Henning created "The Beverly Hillbillies", it was his intention to cast Bea Benaderet in the role of Granny. However, Irene Ryan gave such a great audition that Benederet herself told Henning that Ryan should get the part. Henning agreed, and out of loyalty to Bea Benaderet, then created the character Cousin Pearl for her. He later cast her as Kate Bradley in Petticoat Junction.