Warm milk to 105–115°F, then stir in 1 tablespoon of the honey and the yeast; let sit 5–10 minutes until foamy. If it doesn't foam, start over with fresh yeast.
Add remaining honey, cooled melted butter, Greek yogurt, egg, vanilla extract, and orange zest to the yeast mixture; whisk until smooth and creamy.
In a separate bowl, whisk together both flours, cinnamon, nutmeg, allspice, cloves, and salt until spices are evenly distributed.
Add dry ingredients to wet in three additions, stirring after each, then knead on a floured surface for 8–10 minutes by hand (or 5–6 minutes in a stand mixer) until smooth, elastic, and slightly tacky.
Flatten the dough, scatter dried fruit evenly over the surface, fold it in, and knead gently for 2–3 minutes until the fruit is evenly distributed.
Place dough in a lightly greased bowl, cover with a towel, and let rise in a warm draft-free spot for 1–1.5 hours until doubled in size.
Punch down the dough, divide into 12 equal pieces (about 85–90g each), shape each into a smooth ball, and arrange in a parchment-lined 9x13 inch pan.
Cover and let buns rise 45–60 minutes until puffy and touching; preheat oven to 375°F (190°C) during the last 15 minutes.
Mix flour and water into a thick paste, transfer to a piping bag, and pipe a cross on top of each bun just before baking.
Bake on the center rack for 18–22 minutes until golden brown and the internal temperature reaches 190°F (88°C).
Warm honey and water together, then brush generously over the hot buns; let cool in the pan for 10 minutes before serving.