No. Definitive is when a rider is sanctioned by anti-doping agencies. Up until that point, all you have is speculation/innuendo/beliefs/suspicion/whatever you wish to call it.
(I am reminded of the comments of the moderator at a scientific talk I once attended. The debate was getting a bit heated, at least until he trotted out a series of slides showing bridges of various construction, i.e., a modern steel suspension bridge, a wooden bridge, a plank-and-rope footbridge, and a tightrope. He then drew analogies between these and how scientists use "I know", "I believe", "I think", and "I feel" to illustrate the strength of their convictions re. a particular conclusion.)