Could be a nice change of pace.
As it is written, a sensible party will have little difficulty achieving their goal; the challenge depends mainly upon the ease with which they can discover each dragon's fancy.
Tjamaladara might detest falsehood, being straightforward; she could test the PCs' mettle as well, deciding upon their performance whether they're worth wasting time at all.
Shadrevaen could react favorably to behavior patterns seen in romanticized works, and less well to a pragmatic approach. A knight-in-shining armor or minnesanger might be the best negotiator, especially if putting on sufficient pathos. She could want the PCs to capture a famous bard for her (and locking him in a cage like a bird).
Zaulphiria, even though vain, might have the tooth of suspicion gnawing at her - what if she no longer looks her best? Carefully worded, an offer of lasting beauty-enhancing treatments would be worth a ton of bonus points. Badly phrased, it would get the PCs a massive minus.
I like the image of an insidious tequila worm that is up to no good. I picture him with a tiny sombrero on his wormy head.
The sole objection: Donovan, being a competent wizard using suggestion magicks should have found it quite easy to go all Jedi on the investors. "You WANT to revise the contract. The original Timmy is FAR better. No one will LOVE you unless you abandon this folly."
It does not feel like revenge - after all, the girl did nothing to actually wrong Sean the Failure.
Also, this kind of petty envious hatred is so common that likewise the Skrelleth demons would inadvertently be an everyday problem.
Also, the >curse< thing is unfitting for such petty critters - I see them rather physically switching bottles, spilling poison ivy extracts into a bath, or carrying a diseased cloth to their victim.
Actually, we had a 30 with this theme....
Only, it got to 101.
What about simply adding these to that list? (Also, some of these are duplicate of problems on Scras' list).
Minor issue: legionnaire's disease is caused by a bacterium, not fungus.
With the right kind of players, this can be an interesting plot hook.
Though, the mechanism of wish-granting could be subtler in some instances - at time it reads like a marketplace ("What does a leg get me?"); also, I can envision it sticking longer to one wishing person who has a great dream, helping him but consuming him in the end.
Plot hooks are good.
All in all, a good sub.