After breakfast was over, Bruno was required to report back to the Kaiser, the man had after all made a personal request of him to become closer to the Tsar, and while Bruno had achieved some modicum progress in this regard it was not exactly like a strong bond of friendship could be built overnight.
Unless, of course, there were some extraneous circumstances like Bruno saved the Tsar's life, or they endured some trauma together like a survival situation, or fighting on the battlefield. And none such occasion had occurred during his time in Russia.
Because of this, Bruno appeared at the Kaiser's palace where the man was clearly expecting his arrival, as he had quickly been welcomed into the home. Bruno saw the Prussian Princess Victoria-Louise upon entering the building, and though he tried to say hello to her, she simply glared at him as if he was some pile of refuse before walking off while pouting, all without saying a word.