Stopping the pattern of pyramiding is much harder than preventing it from the start.
The "bumps" that are there will always be there even once new growth comes in smooth.
You can go to the sulcata section read Tom's threads on keeping them and he answers all your questions on humidity , temperatures , and dietary needs . Nothing will happen to his shell but becoming more bumpy .
Here is a picture of my sulcata that has been kept at 80% humidity and a no lower than 80 degrees with a 95 degree basking spot .
I use these bad boys to measure the humidity and temp. (Temp is displayed at the bottom, Pistaschio is just blocking it ) they are available at just about any home improvement store or Walmart. I got mine on Amazon for $10 [THUMBS UP SIGN]
If you are asking if I have the same type of tortoises as you, yes, I have 2 sulcatas. Mine did look like yours when they were the same size and age, because the pet shop I got them from told me the wrong information on how to raise them.
Tom put a very good link in his post about caring for sulcatas. Please read it if you haven't already. If you make changes now to your sulcatas' enclosures, you can prevent any further pyramiding from happening.
It will depend on your enclosure . You will have to test out wattages of lamps to hight of the lamp. To keep your temperature at a good 80 degrees you will need a che with a thermostat . If you go to the custom search tab look up Tom's thread on closed chambers . It will tell you what you need to do .