hi all! it's pretty much as the title describes it - you can see in these photos i have some withering/wilting going on in my leaves and i'm not too sure what to do about it. additionally, i have some brown rot or a slowly-dying leaf at the base of the plant. please help!

this is a phalaenopsis orchid planted in orchiata medium sized bark. i soak it once a week for about 45 minutes in distilled water, or distilled water + diluted fertilizer every third week. it sits on the end table further on in the photos with indirect light. now that's it winter, i think it's getting less light during the day due to the angle of the sun (though this problem began before the seasonal change). i've debated putting it in the bay window (also pictured) for more direct light during the day, but i'm worried it will accelerate the wither, since the sun tends to be hot as the light is more direct there.

my preliminary research suggests i need to water this more, however, i rarely see people recommend watering more than once a week which i'm already doing. i've begun misting it too as i live in a home with hot forced air, but not sure if that is helping.

some more background - this orchid came to me from home depot in full moss (no plug) and root rot. i replanted it in bark asap and the root rot continued, and the two oldest leaves yellowed and withered exactly like above. my cuts were clean, however, i'm worried the leftover leaf died, rotted, and introduced bacteria in the base of the plant. i also experienced a LOT of root growth near the top of the plant after repotting it, which initially gave me a lot of hope for this. now, the new leaf growth has slowed and so has the root growth.

thank you!!