All you can do is go and ask the immigration office where you are staying. As others have said I wouldn’t argue with them to be honest they don’t care what reason you have. Have you asked the Germany Embassy in Thailand if they can give you a letter to say you can’t go back to Germany.
My suggestion is to come over to Thailand for a couple of months look at different areas do your homework on how much it will cost to live there food, rent, buying a vehicle or renting one. School for your child as they will have to go to an international school.
A major point is how are you going to support yourself.