Are they still in the pots? I would wash what is left really good to get the vinegar and oil off them. Oils will burn the leaves if the temps are over the mid 70's. Since they do not have leaves, the canes are going to get sun burnt. Partial shade should help til they grow new leaves.

Next time, I hear spraying the foliage with water is all you really need for the mildew, that and time for the plant to grow later and better throw it off on its own.

Save the vinegar for weeds. Roses are pretty tough, bet these two come back.

No, they are not in their pots. I planted them the day after I purchased them about 2 weeks ago. I have washed them down, I do regret that vinegar mix! Hope you're right about them coming back!

Vinegar is a herbicide! Oil and soap can burn foliage in hot weather. Please do not use these jackleg kitchen-pantry mixtures that you might see on the internet. In the eastern US, powdery mildew is usually not a severe problem and is easily controlled.

Probably your plants will recover just fine if you are patient and do not "help" them too much. Just water thoroughly every 4-7 days depending on the weather and when the soil surface is dry-ish. Put down a 2" layer of mulch.Don't fertilize until they are growing out happily, and then use less than the label recommends. Best wishes, and come back for advice any time.

If they have no leaves and it is hot, it would help to give them some shade for the heat of the day, not super pretty but a plastic chair over the plant is an easy way.

There are some home mixes that are probably fine on your roses, but if you find one you want to try, ask here first. Usually some one has already tired it and either knows it works or it doesn't. There are a lot of "organic" mixes posted out there but people often leave out big details on usage and side effects on different plants and how they effect the long term overall health of your garden.

Seems like many of the rose issues we have on my coast could be helped with a spray of water no need for other additives :)