OP, you said that your mechanic hasn't been able to look at the car but that there is 0 compression. Did your mechanic just listen to the engine crank and then give you that opinion?
If your mechanic did a compression test, and all cylinders were 0 psi, then I agree with the others that timing is the likely issue.
However, if your mechanic only listened to the engine crank, then I would bet that your timing is perfectly fine and that there is just enough water in your gas tank to keep the engine from starting. Out of curiosity, do you use gasoline with ethanol added to it (E10, E85, etc) or do you use 100% gasoline?
Hope it turns out better than expected and would love to read an update as things progress. Cheers!