Plague village idea

So the players are travelling and have to stop in a town to resupply/rest/etc, but they find out that a lot of the townsfolk are afflicted with some sort of plague. It's a small town so there's only one apothecary that'd pay them a lot if they can help distribute medicine to various folks that have been diagnosed. Those that get too ill are taken to be quarantined in an old mine.

As they go about town, they can gain clues as to what's causing the plague. Various ways to go about it, including medicine checks on the people they're delivering to, social checks asking about how to came about, investigating empty houses, etc. The more successes they get the more information they learn about what's really going on. Some info includes: The people you're delivering to aren't actually sick. Someone died of sickness around the time the apothecary came to town. People who go to quarantine never come back.

The apothecary won't be in his office, he'll be in the mine. If they confront him, they'll find him in a chamber with a restrained female vampire thrall, feeding her. He'll try and fight, but he won't fight to the death; if he's brought low he'll beg and bribe for his life. A vampire came through town and turned his daughter, so he's been knocking out townsfolk to keep his daughter fed until he can find a cure somehow. The players can then choose to do whatever they want. Kill them both? Turn them into the town? Let him continue in exchange for money and possibly a magic item? Find the vampire responsible?

If they don't confront him, he'll come back to his office and diagnose them as infected. He'll then try and give them medicine to knock them out and take them to his daughter, and the same fight will ensue but the players might be debuffed. If they don't take the medicine he'll fight them in his office and the players can find out about the mine after defeating him.
Some details are missing cuz this is pretty much just based off memory, but yea