Riera tried to broker a fragile - and transparent - peace on Thursday, insisting he wanted to stay.
Yet that only came after Spartak Moscow, who were set to sign him on loan, refused to meet his demands for double his current wages.
Benitez, whose side visit Birmingham tomorrow, revealed: "We still have some time until the end of the Russian transfer window so we'll see what happens.
"I didn't see his latest comments but for me, on the day before a massive game when he was talking this way it was disappointing.
"It was especially so when he was saying things that weren't true.
"He also said he wants to play, that's why he had to go, but our fans are not stupid and they will know what's going on."