According to latest HAPAG-LLOYD statement, 5 crew were transferred back to YANTIAN EXPRESS, presumably on Jan 11. Fire said “to be largely contained and brought under control”.
Most probably, crew were transferred to container ship to facilitate towage and for a general reconnaissance. Maybe they remained on board, maybe they returned back to SMIT NICOBAR. It does seem like towage is ongoing, however slow and difficult. Average convoy speed on Jan 12 is 3 knots, with some 1100 nm distance to Halifax, assumedly port of destination, it’s some 2 weeks sailing, if weather permits.
Full chronology: http://maritimebulletin.net/2019/01/04/container-ship-yantian-express-on-fire-in-north-atlantic/