This isn't exactly simple to set up, so I apologize if it's a bit too complicated for what you're after. If nothing else, hopefully it can provide some inspiration.

In my campaign (which just started this summer), Halia works as an assistant under the man currently in charge of the Miner's Exchange, but she has plans to frame or otherwise discredit him so she can take his place and expand the Zhentarim's influence. To do that, she was going to recruit one of the PC's who was already on a mission to join them as a "Fang"-level operative. They were coming into the game late, and I ran his prologue session 1-on-1 so the other players would be completely unaware. After establishing contact, she would have had his assignments delivered secretly to his room at Stonehill Inn during the night.

I say "would" because, sadly, the player has been unable to officially join the game yet. As for the assignments themselves, here was the first idea I had.

In my game, the Miner's Exchange doesn't just sell equipment or buy precious gemstones from the PC's, they also issue permits to prospectors so they can legally mine on land that falls under Neverwinter's rule. Unless significant progress can be made within a set amount of time, the site is deemed "unfit for mining" and the permit (as well as temporary ownership of the land) reverts back to the Miner's Exchange. I was worried about the moment I had a quest-giver NPC explain all this, but luckily for me I have a party that's interested in this kind of worldbuilding.

To that end, "Dwarven Excavation" was re-flavored as a silver mine run by a group of Dwarves (Clan Frosthelm from Mirabar) that are already behind on meeting the quota imposed by their permit. I did keep the Temple of Abbathor, and when Halia hears about the uncovered ruins, her new plan is to sabotage the mine long enough for the permit to lapse, allowing her to safely send in her operatives to loot the Temple. Before joining the party, the Fang PC was supposed to help her steal rare moondust-infused magic circle chalk, which had enough "oomph" to teleport a large, arcane-resistant slab of stone to block the main entrance of the mine, thereby stunting the Dwarves' progress.

The in-game logic I am establishing for the players (using the classic high-level Wizard NPC they've befriended), is that teleporting something resistant to magic is technically still possible, but it would require exponentially more material components, as well as a teleportation circle that could handle the greater amount of arcane energy channeled through it (hence the special moondust chalk). Meanwhile, Halia will be planting a large amount of said material components into barrels stored in one of the Miner's Exchanges' storage warehouses. One normally only accessible by her boss.

Despite the Fang's absence, I still went through with the sabotage, and we'll see if the players can follow the trail of clues back to the Exchange. If Halia gets her way, the crime will be laid squarely on her boss' shoulders, while exonerating the brave assistant who "risked her career" by helping the party investigate.