Ficus lose a lot of leaves in fall and then fewer over the winter. Are the affected leaves on the side facing the window, bottom half of the plant, top half, evenly spaced everywhere?
FIcus are good at telling us when they are unhappy. But, unless you change just one thing at a time, its hard to say what the cause really is. You gave it a new environment, a new pot and soil, new exposure, then treated it for bugs. Its hard to determine the real cause.
When you bring a plant into your home from the cushy comforts of the nursery greenhouse, its going to suffer. Different temperatures, lower humidity, different light exposure ... it takes some time to get used to the new situation.
Repotting is really stressful for plants, no matter how careful you are, the tiny root hairs are going to be disturbed and need time to heal before the plant can look and feel its best again. Its always best to give a new plant about 6 months of acclimation time and then repot in spring or early summer when you see active growth.
Usually, brown deformed leaves indicate underwatering or sunburn. Ficus like barely damp soil but not dry soil. When the upper leaves brown or deform, the the tree is saying more water please.
Most plants grown in a nursery setting do not live in the sun so have to be acclimated to sun so if the brown deformed leaves were on the window side, it could be sunburn. No, don't move it. New leaves will grow and they will be acclimated and the tree needs the sun to be healthy. Every time you water, give the plant a quarter turn.
Yellow leaves on the bottom part of the tree would indicate too much water. If that's the case, insert the water meter probe as deep as you can to see what's happening further down. Did you put rocks or pebbles on the bottom of the pot? The pot has a drain hole, right?
Pesticides are also hard on plants. Its always a race to see what dies first, the plant or the bugs. That's why its important to follow the directions to a tee but also don't treat what you can't see.
On the whole, I think your tree looks fine. It needs time to sort things out and in a couple months, I think you will see new leaves and overall improvement. In the meantime, good light, good watering practices and no fertilizer (that will add another layer of stress). Fertilize in the spring of 2023 with a complete fertilizer mixed at half strength.
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