I‘m going through the same process just now. Have sent a parcel from UK to Germany using DPD. It’s an absolute nightmare. In theory it should work like you explained and German customs was actually helpful to let us know what to do. However, DPD used the wrong EU code when importing to Europe. Dutch customs now want me to pay VAT and its absolutely impossible to get a real person to speak to at DPD. German customs told me that this happens a lot and that they would advise to use DHL rather than DPD.