The 20-year-old joined the Spanish club on loan from Arsenal last summer and is scheduled to return to the Premier League outfit at the end of the season.
"There is a lot of speculation about Campbell's future," Joaquim Batica told Marca. "He belongs to Arsenal and is on loan at Betis now.
"The truth is that Betis want to extend that arrangement, but nothing has yet been decided. The Spanish club have let Arsenal know their position and let me know too, but at the moment there is nothing confirmed.
"He is very happy at Betis, because all the objectives we set at the start of the season have been fulfilled. What he wants is to play and to grow as a player. He is doing that at Betis. He would not mind staying longer, but sooner or later he will play in London because Joel Campbell is an Arsenal player."
Campbell joined Arsenal from Saprissa in the summer of 2011.