It still looks like it can be saved.
I think we need to provide it with more water.
If the humidity of a growing area is high enough, an orchid can even survive without that much watering. But if relatively dry, then the orchid definitely needs to get water into it - otherwise it will begin to dry out in the way that is seen in the photo.
For maybe a lot of regions, a once a week watering might not be adequate.
It could be considered similarly to somebody giving us 1 cup of water on one day (for drinking), then our next cup of water is only given to us about 1 week later.
With the roots dried out a bit now - in the photo - the orchid still looks ok. Pot it in an airy medium (eg. coarse bark, or scoria, or coarse bark and perlite mix) with very good drainage. And maybe water this airy medium mostly around the outer side of the pot (rim), and less water toward the central part (ie. to avoid getting most of the roots too wet for relatively long periods of time).
Some details here can be useful too ......
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