Hopefully it comes through OK but keep a good note of all the dates/times etc. when you have been in communication with VM about returning the kit and ordered the packaging, sent it off etc.
The VM returns process, like many other VM processes, seems to be highly erratic for some (ex-)customers.
Once you have posted the kit off, keep a careful record of the posting/tracking info as that is the only thing that protects you from being charged if any problems do crop up with the return.