Hi again...
For now I have implement a workaround as a temporary solution until you come out with a fix for this.
I will post my workaround here just in case it's at all useful to anyone.
In my case I only need entry's view.html so I modified the corresponding view file, the display method.
What I do is checking if the current post language is different than the current site's language.
If they are, then I redirect the site for the same post using the post's actual language.
So here is the piece of the code in the display method. This goes right after checking for the $id.
// Temporary Workaround to prevent posts of 1 language to be shown in other languages
// We check this after we have confirmed there is a post id, as if not we need to throw a 404.
// If multilingual is enabled
if ($this->input->app->getLanguageFilter())
{
// If current post's language has different language than the current site's language
if ( $post->language !== $this->input->get('language'))
{
// Get language URL code for the language the post is assigned
$languages = JLanguageHelper::getLanguages('lang_code');
$languageCode = $languages[ $post->language ]->sef;
// Check if there is an Itemid set
$itemid = $this->input->get('Itemid', '', INT) != '' ? '&Itemid='.$this->input->get('Itemid', '', INT) : '';
// Build the new URL to redirect to the correct language for the current post
$redirect = 'index.php?option=com_easyblog&view=entry&id=' . $id . $itemid . '&lang=' . $languageCode;
// Redirect
$this->input->app->redirect(JRoute::_($redirect, false));
}
}