The site and source is rubbish but the information is accurate and being reported by these typical "leak" style sources. Combined cycle engine has been tested and flown for "extended" time.
His post adds nothing new. The test flight has been covered here at both the space program thread and hypersonic thread using credible sources. His sh!tty article adds absolutely nothing new, cites no sources, not to mention is a stupid machine translation, and he's been told to stop by multiple people – including a mod – for precisely the same reasons.