As stated in the OP, there were many Challenges back in the days, from the 1930s to the 1960s in a 1st 'era'...
As you can see, GJJ vs Luta Livre or GJJ vs JJJ or Catch Wrasslin´ (in George´s fights) were not that great for the family.
It´s indeed quite fascinating, since there was a significant qualitative shift from the 'traditional' Luta Livre Generation (Ivan Gomes, Euclides Pereira etc...) who was more into 'pure' grapplin´, to the 'modern' one (which had more emphasis on MT first, because of the influence of fighters like Flavio Molina for instance.. they then decided to focus on the ground game...)
The 1950s-70s Generation was from the Northeast of Brazil, while the 1980s Generation was mostly from Rio de Janeiro jus´like them Gracies (moved to Rio a long time ago)..
No real contact between the 2 Generations, so the Modern one learnt with guys like Roberto Leitao or Brunocilla:
during the BJJ vs Luta Livre Challenge (1984), the Luta Livre team had to hire Brunocilla as a coach to enhance their ground game (they were all very raw, Marco Huas was the best of the 4, Tadeu could only be considered a blue belt for instance)
In time, Tadeu was dominatin´Henzo when Lights went out... while Huas had a very close fight vs Pinduka, one of Carlson´s toughest BB (Huas was aprox. 175 lbs, according to him [tough to assess, watchin´the fight, I would say he was a MW though...] while Pinduka was probably a LHW]... Both claimed victory...
Huas rematched Oleg in Brazil and dominated him, since the 1st fight was controversial:
http://forums.sherdog.com/threads/the-day-oleg-forgot-about-the-special-rule.3853539/