One person's mold is another person's mycorrhizae
First, welcome to the site!! Second, it is sometimes hard to tell the difference, visually, but it appears what you are looking at isn't mold at all, but rather mycorrhizae, which is symbiotic fungus that grows in most soils, and which forms a positive symbiotic relationship with plants. Usually you will only see it deeper in the soil (for example, when you are repotting) because it requires moist conditions and does not respond well to sunlight. However in your case it appears you are keeping the soil well-watered and heavily fertilized, and the soil is responding positively. You can see how the mycorrhizae is growing within/amid your moss and doesn't appear to be harming it - or your Carmona, which looks extremely healthy. Note that some mycorrhizae will send out fruiting bodies in the form of mushrooms.
However... be careful with your tree to make sure you don't turn the corner from "just enough light and water" to "too much water and not enough light" particularly as we are going into the Fall and Winter and your photoperiod drops. On bright warm days you might want to pop open the window and let your tree get direct sunlight. Keep an eye on the soil to make sure it doesn't become saturated and waterlogged - and that your tree doesn't start suffering dead/rotting roots as a result of hypoxic soil conditions.
Otherwise I would say that everything looks great!
