So I picked up an Amyae yesterday. I got him off of craigslist, the person I got him from really made sure I did the research before getting the gecko. I set up a tank and everything before I got him, and the guy really knew his information. But he told me that the gecko was born without a tear duct in it's right eye. He used to go to the vet to have it drain, but it'd leave a small hole for a while that'd allow bacteria to get in. Him and his vet decided it was too much of a risk, especially since the gecko was on sand, and stopped draining it. From the sounds of it, and I might be wrong, but I guess the eye will swell up so large that it drains on it's own? I suspect this is why it currently has a layer of sand on it. The gecko was like this when I got him, and I was told that the sand will dry and fall off on it's own. The gecko was licking it a fair amount, so I'm guessing that the gecko eventually just pulls it off?

I apologize for the bad pictures, I had to use my phone while my camera is being "borrowed" and likely buried in the sand at the beach...
And although you can't tell here, his left eye is actually completely normal sized and colored, and definitely works.
I was told to take him off of sand for the time being, I'm really hoping that won't be a bad move as I've heard it can stress them out. He has sand in the corner of the tank in a fairly good sized pile so he can at least dig a little. Lots of cover, you literally can only see 10% of the bottom of the cage. Temperatures are roughly 89-90 directly under the basking spot, down to 78 on the other side of the cage. He's in a 20 gallon long, however I have a 40 gallon tank I can move him to. I've put up cardboard around his tank so he can't see me when I'm in the room.
I'm a bit confused as what I should do. I picked up a saline solution for sensitive eyes in case I had to give him some eye drops to loosen up the sand. But I know he was stressed enough as it is, since I only brought him home last night. He was getting to the point that he'd wiggle the tip of his tail every step it took to get him to his cage. I have been trying to avoid messing with him since.
The guy I got him from didn't seem too shocked that the gecko has a layer of sand over his eye. Should I just wait it out and let it fall off? Should I give it eye drops to help loosen it? I don't think it'd be an option to try to get it off myself, honestly the gecko has been through enough lately than to top it off with that.