I’ve been having similar problems with denoiser and they’ve always been about incorrect sequence settings. Your video processing must be 8bit and you’ll have to make sure you have the correct field dominance. For example I tought I had the upper fields first, but it came out to me that compressor had been converting my footage to prores without any fields. Loosing the fields wasn’t a problem to me but it sure did mess up my settings, because half of the footage were converted to prores with adobe media encoder which, as a default setting, keeps the fields.
Simple things are often the hardest ones to understand.