Second time around

being fit and muscle memory is different. Now there is muscle memory for weight training

I am very confused on what you are asking though?

I guess I'm asking if it's easier to get toned back up once it's all been covered up by weight gain if you've been toned before

So basically when you say tone what does that mean first off. Lets use healthy balance of body fat% and weight. SO your were healthy BF% then got big. You are wondering if it will be easier to get smaller? I would say no. BTW my first pic on the left was when I a lot of people were saying I was fit.

Good question, I am kind of wondering the same thing. I do think you have the term muscle memory confused though, it has to do with your muscles "remembering" how to do something but not necessarily impacting the actual impact it will have on your weight loss or fat %. For example, once you've learned how to ride a bike, you pretty much always know how to ride a bike. If you stopped riding a bike for a year than go back to it, you won't burn more or less calories this year riding the same bike than you did a year ago simply because you still know how. I think that is the simplest explanation of muscle memory. If you're lifting, I would imagine you will be able to be more efficient at it, and will use your muscles more easily than when you were first learning, but I doubt if that will change how your body actually responds to the efforts. I'm not sure I'm 100% right on this, or even it it's making sense.
Maybe, because you will be using your muscles more efficiently, you might see quicker results than the first time around, but I don't think you could attribute that all to "muscle memory." It seems like a chicken or egg first kind of situation.