I have the exact same EXO Terra as you, the rest of my enclosures are custom wooden ones, but I have my rescue boy with MBD in the EXO Terra, and you absolutely need a long tube
UVB light, preferably a 10.0 (never 5.0) T5HO with a reflector behind it. That 13 watt coil is pretty worthless, and if you had it on top of the mesh lid it was blocking about 40% of the already too weak
UVB light, and that bulb stops emitting UVB after 6 months. So you really need to get a new tube ASAP, cause he's had very little UVB.
No, it won't hurt his eyes, generally those coil bulbs are what cause serious eye damage.
If you buy a 10.0 T8 UVB tube (weaker than the T5HO) it must be mounted under the mesh lid and inside the tank, and within 6-8" of his basking spot to be effective, and the T8 must be replaced every 6 months. With that particular EXO Terra, it's far too low to mount a tube fixture inside, under the lid, so I'd recommend getting the 10.0 T5HO tube and matching length fixture, either an 18" or 24", because it can sit on top of the mesh and only has to be within 11" of his basking spot, which is good with that tank, just sitting it on top of the mesh DIRECTLY OVER HIS BASKING SPOT will put it within the correct distance. And the T5HO tube only needs replaced once a year.
One suggestion I will make is to get both your new UVB tube and your bright white basking bulb right alongside each other on the Hot Side of the EXO Terra, both directly over the basking spot, so he gets both at the same time while basking. This will replicate natural sunlight as closely as possible. I noticed you have the two lights on separate sides, with the UVB on the Cool Side, and that does him no good at all. This is the advantage of a long tube UVB with a reflector behind it, you can center it directly over the basking spot and right alongside the basking light over the Hot side to make his basking spot optimal, but the
UVB light will still be reflected all over the tank if you buy a 10.0 T5HO tube.
Check Amazon.com, I just bought 3 22" 10.0 T5HO UVB tubes for $23 a piece, and I know that once you search and choose the actual UVB tube, they will show you a package deal that includes a matching 24" tube fixture that is rated for a T5 tube at a great price, best price I've seen.