Playing through Thief Gold with HD Texture Mod and Tfix 1.27b
On the Escape mission I have got to the mansion, I have watched on youtube and read through the walkthrough on gamefaqs by Taffer but I cannot find my gold from the previous cathedral mission. The insect man in the mansion near the bar I killed has no gold pouch for me to loot. The walkthrough and each youtube walkthrough I have watched show a loot pouch. I have tried a few previous saves and no matter what when I drop it, there is no gold.
Am I screwed going forward not being able to buy as much?

share a save.

While I can't help with the issue you're having, the game is made so that the default items you get before the mission, without buying any additional ones, are sufficient. Even Lytha wouldn't buy anything - and this is a quote, "Garrett should save his money instead of wasting it with items that he doesn't need at all".