Do my Russian Tortoises shells look healthy?

I have 2 Russian Tortoises and the large tortoise's shell (on the left side of picture) is getting soft in the middle but it almost looks as if her shell is just growing bigger, and it might be a natural thing. The smaller male tortoise has a ring around the top of the shell the black spots are starting to fade and look really dry. Here are the pictures of both of my Russian Tortoises. They have the proper UVB lighting and they have a UVA basking spot lamp. I give them Reptile Calcium with Vitamin D3 powder on their food. They eat a variety of vegetables and fruit, including carrots, kale, romaine lettuce, cabbage, strawberries, tomatoes, spinach, bananas sometimes. The fruit is not given to them every week. They are fed every day and I put them in water every other day to soak and to stay hydrated. I've taken them to vet a few years ago and she said that it was from the shell growing larger, and it was normal. Just wanted to see if anyone had any input. Thanks!

Sorry about the pictures, these are the best ones that I could get to fit together.