It is fine to refrigerate the cloud cream, provided you have already frosted the cake with it. That is, don’t make the cloud cream and then refrigerate it in a bowl, expecting to frost the cake the following day. Best to frost the cake when the cloud cream is first made.
You could complete the whole cake 24hrs ahead and refrigerate until an hour (or maybe a little longer) before serving. I have done this several times with the Strawberry Maria, it always works.