Approval documents for a scooter IVA JL50QT-2

Hello together, I have received a scooter from an acquaintance for my 15-gen son. Unfortunately it turns out that it is only a 25 km/h scooter. Now I want to open this at our village workshop at 50 km/h. KfZ Meister has already agreed with TÜV that it is no problem if a new CDI is installed, but it requires papers from the same scooter that is already registered as 45 km/h to extract some data (gas values etc.). I have been uploaded in the appendix. Does anyone here in the group have an idea where I can get these documents, or does one of them have such a scooter and can provide me with a copy of the admission? Thank you in advance. Greeting S.Selich