SOS my moms 8 months old turtle got bite by my bad dog!

Question
We don't know what kind it is, we only only it is 8 months old, rescued from side of a busy highway.  It could be a tortoise or a turtle.  It was stolen by my very bad dog from the turtle's box very briefly, but when my mom got it back, she found 3 cracks on the poor turtle already.  one crack is on the top shell, and two on the bottom shell.  The turtle is still moving its arms and it seems its head escaped harm.  I was told by one vet to wrap the shell with gauze and wet the gauze to keep the wounds from drying out, but by another to keep the wounds dry so that bacteria doesn't grow.  So i am not sure now if the wounds should be kept dry or wet???
The vet who said to wrap it moist gauze also suggested antibiotic cream and iodine cream on wounds.  Would you know what would be generally available to get from pharmacy?  
My mom couldn't get to a vet because she is over 70 and doesn't drive.  And she is in New York while I am in California.  So taking the poor turtle to a vet isn't possible right now.  
Thank you for all your help, I haven't had time to read all your answers.  Do turtles who got hurt and got cracks on shell have much chance to survive?
Thank you.

Answer
I saw your other note first. I am sorry for your loss.

If you have the chance to help another turtle, the better plan is to move it to a safe location near where you found it and let it go on with its life. Catching wild turtles just does not usually work out as well as we want.