There's no need to imagine. Anti Cuba politics in the US is a bipartisan policy.

From the article:

"It would be a step backwards, a sad decision, if the next summit is again affected by the ... absence of many presidents because it has been decided to exclude Cuba," said Argentine Foreign Affairs Minister Hector Timerman.

In the interest of regional unity, "the best thing that can happen ... is for Cuba to participate," he said, adding that it would make it "very difficult" for Argentina to take part in the summit if Havana is snubbed again.

Brazilian envoy Jose Felicio echoed those sentiments, calling Cuba's inclusion "a necessary condition" for "the continuity of constructive dialogue" towards greater integration.

His Bolivian counterpart, Diego Pary Rodriguez, was even more blunt, saying "if Cuba is excluded, we consider ourselves excluded as well from the next summit of the Americas."

Other countries also declared themselves in favor of the proposal, including Chile, Mexico, Nicaragua, Guatemala, Guyana, Peru, Trinidad and Tobago, Uruguay and Venezuela.

Seems like Cuba doesn't want to rejoin the OAS. Here's what happened the last time in 2009, for the forgetful.

<snip>

HAVANA, Cuba (CNN) -- Cuba will not rejoin the Organization of American States, even though the multinational organization has lifted the 47-year-old suspension of the country's membership, a Cuban official said Thursday.

Ricardo Alarcon, president of the National Assembly, made the announcement to reporters. Former Cuban President Fidel Castro had said earlier this week that Cuba had no interest in rejoining the 35-nation group.

<snip>

http://www.cnn.com/2009/WORLD/americas/06/04/cuba.oas/

It's not impossible something changed somewhere on the planet in the 5 years since then.

The Cuban government is implementing reforms which allows more and more people to own more private properties, and is opening itself to more international markets. Since the government's needs capital, and they see that Venezuela is becoming increasingly less capable of maintaining their economy, they have to resort to new sources of wealth. There's an interesting 2012 BBC documentary about it which gives a more in-depth look about how the reforms are changing Cubans' lives. Check it out: http://m.

Looks like it.

Esteban Lazo Hernández is the current president of the assembly.

Also, from the 2009 article you linked ...

Group of 77 will Condemn US Hostile Policy against Cuba
June 12, 2014
Written by Radio Rebelde
Published in Cuba

The final declaration to be adopted by the upcoming Summit of the Group of 77 plus China will condemn US’s unilateral and offensive actions against Cuba, including the most recent and subversive Twitter program Zunzuneo.

According to the island’s permanent mission at the United Nations, the draft document strongly rejects the sanctions imposed by North countries against nations in the South, based on issues like terrorism, traffic in persons and drug traffic.

The forum, made up of 133 nations, is also expected to reject the use of information technologies in violation of international law and in this regards the Group of 77 plus China has noted that the US-sponsored program known as Zunzuneo against Cuba exposes its illegal use of such modern technologies.

The summit will also back Havana against Washington’s blacklisting of Cuba as a state sponsoring terrorism, which is an excuse to justify the over-50-year economic blockade against the Cuban people.

The Group of 77 agenda also includes initiatives about climate change, migration, agriculture, health and education, the millennium goals and the post 2005 working agenda for sustainable development.

http://www.cubasi.com/cuba/item/535-group-of-77-will-condemn-us-hostile-policy-against-cuba

(Short article, no more at link.)

your TwiHards repeat it on every forum (of course, the Bieber/1Direction approach has worked so well for over 6 years--why change?)