https://en.wikipedia.org/wiki/Cowardly_Lion#Books
There is quite a strong set of lion portal symbolism thorough the years.
A girl has a dream about another reality with some strange and familiar characters. https://en.wikipedia.org/wiki/The_Wizard_of_Oz_(1939_film)#Plot A Tornado serves as the portal into this other reality where a Cowardly_Lion lives.
"In 1965, in an attempt to update its image, MGM recruited Lippincott to create a more contemporary logo.[13] The result, a circular still graphic of a lion known as "The Stylized Lion", appeared at the beginning of two films in the 1960s: 2001: A Space Odyssey..." https://en.wikipedia.org/wiki/Leo_the_Lion_(MGM)#Leo_(1957-present)
Of course this MGM movie would have a portal, AKA the Star Gate.
https://en.wikipedia.org/wiki/2001:_A_Space_Odyssey_(film)#Star_Gate_sequence
"Theatrically released on October 28, 1994, by Metro-Goldwyn-Mayer (MGM)..." https://en.wikipedia.org/wiki/Stargate_(film)
https://upload.wikimedia.org/wikipedia/commons/6/60/Bridge_Studios.jpg Of course the TV production would also have the lion portal connection. https://en.wikipedia.org/wiki/Stargate_Universe#Writing_and_filming