Le Guennac is now asserting that he and his wife are "distant cousins" to Picasso's former chauffeur, Maurice Bresnu, who also said that the artist had given him many gifts.
Bresnu's widow inherited the paintings after his death in 1991. She died in 2009 and her heirs have put them up for auction in Paris on Thursday.
The sale was stopped on Tuesday after the negative publicity surrounding the Le Guennec group of paintings.
"We are six heirs to this collection that we did not know existed until this cousin died," said Danièle Le Guennec.
Police are now holding the Le Guennec paintings.
She added that she did not know about the connection to the Bresnu paintings as she and her husband had not seen the Bresnus for a long time.
"This business is happening at an unfortunate time, even if we're serene because we have nothing to hide," said Daniele Le Guennec.
Le Guennec said he installed alarm systems at a number of Picasso's residences during the last three years of the painter's life. He maintains he was given the works as gifts.
Picasso's heirs are challenging Le Guennec's assertions, noting that the painter guarded his own works and was sometimes reluctant to sell pieces.