Yes because intelligent people are likely to be good at both. That doesn't mean they're remotely the same thing.
Working memory is how much you can remember. Not how much you can visualize.
E.g. the typical test of working memory is telling you a long string of numbers, having you wait a minute or two and repeat back as many numbers as possible. The waiting is the key. If you had the string of numbers right in front of you then it wouldn't be testing working memory.
I'm sorry but you don't know what you're talking about.
