You do not need to drive home just for this. You can avoid a warning or fine in Germany if you can prove, for example, that your vehicle had a valid inspection when you left Germany and has remained abroad since then. This often happens when motorhomes or caravans are parked for long periods at campsites abroad.
In such cases, an inspection report from a foreign testing center may serve as proof. However, this does not replace the official German vehicle inspection (HU), which must be carried out immediately after returning home.
By the way: Foreign authorities are not allowed to penalize an expired HU.