Nurul Islam, accompanied by 45th BGB Battalion acting commander Maj ATM Hemayetul Islam and Kurigram Public Prosecutor Abraham Lincoln, returned around 8:30pm Monday.
Lincoln told reporters that a seven-member bench of judges of the General Security Force Court at BSF Sector headquarters in India's Cooch Behar recorded Islam's statement from 10am to 4pm.
The judges and state prosecutors conducted cross-examinations and Islam answered everything properly, the lawyer said.
BSF's Constable Amiya Ghosh, the only accused in the killing, was also present in the court.
Islam said he was asked many questions. "I answered all of them. I told them that I saw Felani getting shot with my own eyes. I also identified Amiya Ghosh who shot her in court."
"It will cause unbearable pain if I don't get justice. My daughter's soul won't rest in peace."
Lawyer Lincoln said, "We have done our part perfectly. Now we wait for the verdict."
Indian border guards shot dead 15-year-old Felani on Jan 7, 2011 while she was trying to cross barbed-wire fencing near Choudhury Haat with her father.
Images of her body hanging on the border fence triggered outrage in both Bangladesh and India.
The trial over her murder had started in August 2013.