I'm going to preface this with an admonition. If you don't feel like being admonished - tough.
You bought an animal without doing one iota of research on it's needs. Don't give med any lip and tell me you did research - because I've seen this story 1,001 time before. You didn't and unless you wake up to the reality and the danger you've placed that monitor in, it's going to die.
This is an intelligent animal with very exacting dietary and husbandry requirements. Unless you meet these requirement, this poor sav will lead a very miserable and short life.
For starters:
(1) Ditch the glass enclosure. It's too small and it is unsuitable for a varanid.
(2) Your basking area is about 40 degrees too cool.
(3) Your humidity is fluctuating because you are keeping that animal in a completely inappropriate enclosure with the wrong substrate.
That sav needs to have a deep substrate soil substrate to dig in. It also needs something that is essentially sealed to prevent loss of humidity. You need to ditch that glass tank.
Reptibark is a completely unsuitable substrate for that animal. Your sav is loosing his toes because he can't properly shed. He can't shed properly because your husbandry efforts are wrong on every level.
Not to sound like a jerk, but you are doing just about everything wrong. It is important that you understand that you are dooming this animal to a slow painful death unless you take the time to research his needs. After that, plan on spending lots of money to make things right.
If that seems like to much for you, find someone who is willing to properly care for that poor animal.
Instead of posting some defensive reply to my comments, take the next two hours of your life and read this:
http://savannahmonitor.org/
It will tell you just about everything you need to know. Read it and abide by it. Again, if you can't abide by it, donate that animal to someone who will.