Is the quest Merchant Escort manditory inorder for the mc to become the countress? if so I am not able to get the quest Merchant Escort at all.
Not mandatory, but how is it impossible? Did you go to chapter 2 without starting the quest, and lost the opportunity?
Got a mercant pass but border imps still say I have no pass guess I am forced to use the ship.
How did you get the merchant pass? If it's in your inventory (you can check among the key items), it should work just fine when you try to go through the military outpost in the north (it's the only thing the game checks, so there is no room for error there).
What is the combo for the goldenleaf basement lockbox?
If you get rid of the rats in the basement and the bats in the attic (you must hire people to do this through Keiko), you can visit both places. You can then read the previous count's diary (attic) and notice a special bottle of wine on display (basement). The date on the bottle is the combination (you need to read the diary first, in order for the protagonist to get a clue and check the bottle's date).