Hi @TheoffNomad apologies for the late response.
I'm also sorry to hear that you were unable to complete the avenge quest.
I can confirm that this issue was reported by another player in the past, however the development team were unable to reproduce it.
Title Update 1.7.0, released on February 21, is the final update to address bug fixes in Assassin's Creed Valhalla. As a result, any new issues reported will not be addressed by the development team. Thank you for your understanding.