The pictures look exactly like a classical Monilinia damage (it’s a shorter name than Brown Rot Blossom and Twig Blight, the length of which probably indicates the lack of awareness; it’s called Moniliose in French and Монилиоз in Russian). Somehow, there is not too much info about this disease in English. However, it is very well known in Europe and extensively discussed in foreign language orchard forums, especially with respect to apricots and cherries. If weather during bloom was cool and wet (rain, fog) and these characteristic symptoms (dying/withering twigs) appear on apricots or cherries within 1-3 weeks after bloom, it’s Moniliose with 99.9% probability. Likely, many “mysterious” deaths of apricot and cherry trees during spring are actually caused by Moniliose.