I think all position variously described above can make some sense, one way or another.
Let's deal with Transport Canada certification first: Point one here is, I am not sure that the Coast Guard fleets needs it (anymore than we, in the Navy need it either). But even if it was required, Transport Canada inspection/certification of Canadian flagged ships only addresses whether the proper pubs, charts, and life saving equipment is carried onboard and up to date and whether all the ship's paperwork is in order. Those certification have nothing to do with seaworthiness and do not address that aspect. So it is of no use in this discussion
Second, Coast Guardsmen, as pointed out by A Sig Op don't necessarily have point of reference for their view. Moreover, unless they are the ship's engineers, they probably don't know enough about it to start with, just like we wouldn't take the word of a naval communicator or boatswain as indicative of the mechanical state of our ships in the RCN. So social media opinions is just gossip - not a relevant fact.
We now come to Lloyd's. First, as pointed out, the survey is a few years old - and in old ship's estimating life time of the hull/machinery is not easy. Yet, the Lloyd's surveyors are professionals who work with limited information (the surveys are usually carried out with the ship in the water - not in dry dock - so many things are hidden to them) and usually do a good job of it. However, they are usually called upon to make a survey in order for the ship to be
insurable. Canada, like most Western nations, self-insures it's own ships. Why the needs for a survey then? Because that survey was done
shortly before the Hudson was turned over to a shipyard for her last refit ( the one that was screwed up).
That survey was made so the yard could insure the ship while she was in their custody. It likely took into consideration the expected result from that refit work in coming to its conclusion.
Finally, I note in the Davie letter declining the work an important point they raise: the "reputational" risk of taking on this refit. To me, that is the key: Davie has built up a good reputation in the last few years - since it came under English management - and the last thing they need, even at the cost of $20M, is to lose reputation/cred. as a result of trying to fix a ship not worth fixing and then having that ship fail anyway just because it was at the end of its life, and Davie being blamed for that.
The 280's were refitted in the early 1990's and more than 25 years later, some people ( even in these fora
) are still holding it against Davie. Can you think of a good reason they would want to take that risk with the Hudson? I can't.
So I think that it is possible for ALL of the various points expressed above to be either true or validly believed by the people expressing them without looking at Davie having an ulterior motive in this matter.