It, unfortunately, confirmed my suspictions.
It was black rot so the base of the pseudobulbs and the rhizome are is useless because it became black and still firm but killed all of the tissue in the dormant eyes. But I saved the top of the pseudobulbs and leaves which are free of infection. But I know it won't sprout a lead but tissue culture might be an option which I asked in the propagation forum. But I seperated it from the collection before it spread, fortunately.
The Cattleya intermedia is doing good as it sprouted three leads as the main lead actually had its eyes scorched, but at least it won't be rambling with one growth going in circles. But the plant is keeping the main lead and it has a sheath.