I’d leave the flower spike until the attached keiki (baby plant) develops roots that are at least a couple inches long. If anything happens to the parent, there’s a good chance the keiki will make it if it has roots.
The daily soaks will probably eventually work, but Phalaenopsis are slow growers so be prepared for it to take awhile. Between soaks, try to find a bright location that doesn’t get any direct sun.
You can also try potting it up, especially once the new root gets an inch long. I’ve potted up my Phalaenopsis that need to regrow roots in 3 inch size clear slotted plots like:
3" Slotted Clear Orchid Pot
– rePotme .
I use a bark mix that’s 5 parts small-medium orchiata bark 1 part charcoal and 1 part perlite. There are many different mixes that can work for Phalaenopsis depending on growing conditions and watering habits. If you want a good ready made mix,
rePotme Orchid Supplies has a number of good Phalaenopsis mixes available. Orchid roots need to breath, for me airy bark based mixes have worked best. I’ve also don’t have issues with rot if I let the mix get almost to completely dry between waterings. If you pot it up in a clear pot, you can gauge dryness by bark or root color.
Under my conditions, I found myself watering my near rootless Phals in the 3 inch pots every 4-5 days. You can water by holding the plant under the tap or placing it in a container to soak for 5-10 minutes. If you keep it in a cache pot, let all the water drain out of the bark before returning it and make sure that there is space between the walls of the cache pot and the inner pot to ensure that there is enough fresh air in the root zone.
Also, don’t treat the roots prophylacticly with hydrogen peroxide: this will damage them. And, leave the remains of the dead air roots on since they will help anchor the plant once you repot. It also looks like it’s preparing to drop another leaf, this is part of the plant’s way of triaging itself: it’s getting rid of leaves that it doesn’t have the root mass to support. As long as it has at least one leaf, I wouldn’t worry.