Who gains by this ?
If we assume that Bloomberg has got it wrong and also assume that Bloomberg would not want to dent its reputation by asserting bollocks then a lot of effort must have gone into pulling the wool over Bloomberg's eyes. Knitting that wool is probably beyond the abilities of pranksters and would need to be state actors.
What would a country gain by hurting Bloomberg ? Maybe one that wants to make it harder for us to distinguish between fact and fiction, one that generates fake news that it does not like reputable journalism from showing that the news is fake. If we do not know what is true or false then we become confused and less able to make good decisions.
Another possibility is that the five eyes were in on this and do not want it exposed. This I doubt.