Those leaves look old. I don't know what the lifespan of one leaf is because usually they don't act deciduous and lose all their leaves at one time, they replace some leaves at the same time they are losing some old leaves in the spring (in the north). New growth at the tips of branches, old leaves from the interior. All your leaves look the same sage, -old. I wouldn't expect to grow many new leaves in autumn as the sun diminishes. I see new growth from the center of a cluster (upper right) but not at the tip of that branch. I don't know what that means other than the branch/plant may just be old and underfed.
There's more to "feeding" than just fertilizer. It's almost counterproductive to fertilize a plant that never receives good sun. And air circulation is important, too. The transpiration process is aided greatly by winds passing over the leaves, much like a chimney needs air passing over it to draw smokey air up and out. The faster that air passes over the leaf, the more transpiration occurs and hence minerals dissolved in water brought to the cells in the leaves where sugars are produced with light's energy. Low transpiration uses low amounts of fertilizer and water and produces low amounts of sugars. The best you can get fertilizing in low light is weak, leggy growth. New wood/leaves produces better than old. You need to give it the best light you have, and I'd cut each branch back to one bud/cluster of leaves per branch. It's too leggy anyway with the characteristic straight branches. If you have a south or west (west is best in winter), repot with fresh soil, removing large anchor roots and saving as many as possible tiny, hairy feeder roots. If all the leaves fall off, don't treat it as dead, treat is as alive and resting. Water the crown often enough so it doesn't get bone dry in the leafless state, and don't wet the whole mass, either, that will take too long to cycle to dry when the plant is only transpiring through the bark. Plants like to cycle as in nature: wet, dry, wet, dry. They do not like long wet-cold periods. Do not try to speed up/increase growth in autumn/winter, feed in spring when you see growth. Good luck.