Smashing your way through the ever-repeating trap takes time, and is not even slightly quiet, but deep in the belly of the earth it seems you're safe. No enemies come to harass you as you do so, nor are you assailed by dark magics of the Mournland. There is just the mundanity of the moment until, eventually, you carve through one side of the trap enough that you can now pass by without getting skewered. Half of it - the other side - is still in place and endlessly triggering, but the spears don't reach, and you can pass by unscathed.

Ahead of you, behind the smashed down door, is undoubtedly the main vault, crushed by the great talons and bulk of the monster you slayed. The signet ring burning a hole in your pocket that was meant to grant you access, it seems, wasn't necessary. With your extraplanar paper satchel in hand, you begin to pile in every document you can find - it'd be up to those back in New Cyre to sort through them, after all.

But while only one or two of you can collect the papers, the others have the run of the rest of the vault, and its safety deposit boxes. Some are open, some are shut, but none are capable of holding you out when you have time and unlimited opportunity to make noise on your side.

A full, comprehensive run of the vault's contents, amounts to 'retirement' wealth. The only issue is how to carry it all back.

Spoiler: Vault Contents
Show

While I'm generally fairly free with carrying capacity, here I'm going to ask you to be a bit more selective and careful with how much you're carrying/dragging.

Please also bear in mind what was said about Kundarak paying for Salvage:
“Regardless of its current position in the Mournland, Kundarak property is still theirs by right and law and they have no legal obligation to pay you anything for its recovery - and legally you would have to turn it all over to them, or be accused of theft. The laws governing the Mournland in the Five Nations haven't caught up with the current situation." There might be just a slight edge to her voice here, but it's hard to tell. “That said, it's likely you would be paid a salvaging fee relative to the value of that which was recovered. If they're seen to not pay salvagers for Kundarak goods, the salvagers will keep it to themselves or sell through fences, and the House misses out entirely. If they pay salvagers, it incentivises them to go through the House first."
50 coins (of any type) come out to 1lb of weight.

A total of 515,132 gp worth of coins, art objects, and/or gems, as follows:
490,947 gp in coinage:
37,000 pp
120,000 gp
9,000 sp
4,700 cp
10 gp gemstones (×1; worth 10 gp total):
Malachite (opaque striated light and dark green)
50 gp gemstones (×1; worth 50 gp total):
Chalcedony (opaque white)
100 gp gemstones (×6; worth 600 gp total):
Amethyst (transparent deep purple), ×2
Chrysoberyl (transparent yellow-green to pale green), ×2
Pearl (opaque lustrous white, yellow, or pink)
Amber (transparent watery gold to rich gold)
500 gp gemstones (×3; worth 1,500 gp total):
Alexandrite (transparent dark green)
Topaz (transparent golden yellow)
Peridot (transparent rich olive green)
1000 gp gemstones (×8; worth 8,000 gp total):
Opal (translucent pale blue with green and golden mottling), ×2
Yellow sapphire (transparent fiery yellow or yellow-green), ×3
Fire opal (translucent fiery red), ×2
Blue sapphire (transparent blue-white to medium blue)
25 gp art objects (×1; worth 25 gp total):
Cloth-of-gold vestments
250 gp art objects (×3; worth 750 gp total):
Large well-made tapestry
Carved ivory statuette
Bronze crown
750 gp art objects (×1; worth 750 gp total):
Silver-plated steel longsword with jet set in hilt
2500 gp art objects (×2; worth 5,000 gp total):
Fine gold chain set with a fire opal
A necklace string of small pink pearls
7500 gp art objects (×1; worth 7,500 gp total):
Jeweled platinum ring
6 mundane items:
An extensive historical record in the form of carefully knotted strings
An hourglass filled with sparkling sand
A set of seven candlesticks bearing a god's holy symbol
Several embroidered throw pillows depicting wyrmling dragons
A hogshead (large cask) containing 65 gallons of clean drinking water
A painting by an artist long forgotten by everyone except the dragon

Magic Items:-
Chime of Opening
Scroll of Protection from Fey
Potion of Speed
Potion of Flying
Cloak of the Bat
Ioun Stone, Agility
Ring of Fire Elemental Command (unenhanced)