Can you try this with an extra '/' which I forgot to mention
sap.ui.getCore().byId('DetailPage2--RMap').bindElement('/ZFB_TOUR(Tourende='%20DE%2006268%20Kalzendorf%20%2F%20Steigra',HeaderGuid=guid'0050569E-0020-1ED3-9BDC-7DC7B54ADBFD')');
also I think you need to remove the encoded characters from ''%20DE%2006268%20Kalzendorf%20%2F%20Steigra'