It is a theory however, as you mentioned it is update where ferumbras citadel is established. Furthermore, ferumbras himself needed to still build the tower there, so he might hired people from liberty bay to help him (or convinced/fooled them).
You end up on goroma by a mistake while traveling on boat, but it might be that the klabautermen fooled capitan to end up there, so the packages could be transported - so as ferumbras is father of all klabautermen and then we have cellar which is guarded by demon (and ferumbras is one of few able to summon demons), and we have mysterious trunk at shipyard, then for me it is obvious that it is ferumbras cellar, and also that he somehow still needed to transport some goods to his citadel, which are displayed at his treasure room.
Each ship have it own klabautermen -> ferumbras can control ships when he wants
But if you connect Chantelle and Mr.Loveless to this, who is from venore, then it is quickly to notice, that the trunk is being transported to venore rather than to ferumbras citadel.
And venore does have transcripts talking about shady deals. npc Xed:
"honset" -> "Well, I overheard the boss discussing some shady deals with a man in a black cloak."
"shady deals" -> "Something about a sword only great warlords can use and a rare distance fighting item."
"rare distance fighting item" -> "Yes, but I believe this is nothing but lies seeing that there are only a few distance fighting weapons."
If you look now how Mr.Loveless looks
https://tibia.fandom.com/wiki/Theodore_Loveless - he is indeed man in black cloak.
Xed works at Ironhouse at Venore, his boss is Abran Ironeye.
So we can see, that the ferumbras update continued a little story here in venore, as now we know with who Abran Ironeye makes shady deals - he does them with Theodore Loveless from venore.
What is in that trunk then - it might be something connected to weapons, as this is Ironhouse, but it can be something special for the boss - and we know that Abran Ironeye for instance have a teddy bear, that has been rumoured for many mysteries.
Going on with changes into Venore there was some transcripts added at some point to Ashtamor who reacts with transcript. And Ashtamor is highly connected to afterlife and ascension, and that topic interest ferumbras the most.
"slim" -> "Ashtamor: This man is so old and looks so unhealthy that I expect him to become my customer every day."
He talks about Leeland Slim. The way how it is written is similar to Mr. Loveless transcripts about people at liberty bay. It could mean that the same person wrote those, and the mystery here is around understanding what npcs talks about eachother.
I bring this up to show, that there were some hidden changes going on at updates to npcs, which could mean the stories unfinished in past, might now be finished and waiting to be solved.
This whole scenery is just there to point that there are some shady deals/smuggling going on ships that can be either going to some mystery to venore, or to ferumbras citadel directly. If I would make a bet on it I would say the trunk is connected to venore to a mystery that has been unfinished in past, but cipsoft finished it at ferumbras update so the attention is lost.
Shady deals for a sword and a rare distance fighting item - " seeing that there are only a few distance ".
Update 8.2 solves that, and gives us unobtainable to this day distance weapons.
Is this whole mystery has been bring back to life by cipsoft to shred a new light on solving Elethriel Elemental's Bow or Yol's bow that has no info about them at all?
I would be on Elethriel Elemental's bow, as it has been displayed at Pythius the rotten treasure room, to bring attention of us that a bow is obtainable somwhere there, at beregar, but now after researching a topic about heavy trunk mystery, I belive this is the correct path here, and cipsoft but that bow at beregar to fool us and mislead. Furthermore the color of that bow is same as cobalt.
And as mentioned on comment by Allan Kreed, that label probably is used there to deliver that package somehow.