Of course !! You have to remove that (2 Black Widow Tetra,2 Kulhih) and the female Betta too. Because they all eat the egg if got chance. Or you may put one separator (glass,plastic board) to protect the egg being eaten on the tank (which divided the tank as two environ.) While tending the egg,the male betta is very fragile as long as it won't eat the food at few days.
Also,next time,when you have plan to breeding Betta,the tank should be just having Betta couple but other species. Its hindsight,I know,thus convenient.