Even though ornates are known for being cryptic, with the right scape design, you can work around that natural tendency.
I never like using caves in a bichir setup. Don't allow them to be completely hidden from you, because then they will.
But, you can still give them a place to feel secure by using large driftwood with lots of open space beneath it.
The bichirs if startled will all congregate there, then eventually they calm down and move about their business.