Dear Phoung, roses do not die quickly. Do not worry. Can you post a photo of the base of the plant? If there is no problem at the base, I suggest pruning and then immediately plant in soil.

I think you could still save them but I wouldn't use any chemicals to start with. The most important thing is to rehydrate the plants as soon as possible. Wash away the mold and submerge the whole plants (not just the roots) under water overnight and check how they look tomorrow. If the canes are no longer shrivelled they may be ok...

Putting them in a bucket of plain water is the first step but it should be just that, NO chemicals at all. Trimming the broken roots and any parts of the stem that are black. Provided the roots remained moist during transit they should be Ok. You didn't mention what material surrounded the roots when unpacked or an estimate of the number of days since they were sent from France. In Aust. It is not unusual for delivery to exceed ten days.

Now they are in the ground/pot do not fertilise until they come into strong new growth and keep moist. Avoid excessive watering and you may need to protect them if tropical rainfall occurs.

Provide the sap flows, buds will burst into new growth.

Good luck.

they didn't wrap the root by any, any meterial. It's not unusual for bareroot rose since I got same thing from DA US, took 2 weeks to me and they're perfectly healthy and survived. These rose from France not. the packaging was as dry as your dry clothing.