Complex sentence: It was possible that the bones may have come from the remains of climbers who perished on the mountain in 1962, however a subsequent analysis at the University of Innsbruck strongly suggests that the owner of the Fibula was Günther Messner.
Split into simpler sentences: It was possible that the bone could have come from the remains of climbers who perished on the mountain in 1962. However, a subsequent analysis at the University of Innsbruck strongly suggested that the owner of the Fibula was Günther Messner.