It has already been reported by Russian media. The loss part, not the "by Ukraine" part.
Although some of their news shows seem to be vowing for revenge against Ukraine while still parroting the Kremlin line about how the cause is being investigated.
This is the same playbook they are using for the Bucha murders - "it didn't happen" plays right alongside "it did happen but was perpetrated by the Ukranians". I've read it described as a scattergun approach: the lies don't have to be consistent, or even stand up to the slightest critical scrutiny, you just spew out as many as possible trusting that one will stick.