I can well understand that a smaller place makes it appear more comfortable and personal. If I was confident the place had the same or better equipment, staff and timescales it could be tempting.
Although, as you already have the date of the biopsy at the hospital and Christmas is approaching I'd be wanting to get it done. There are possible advantages of having all the diagnosis and treatment at the same place. Dividing treatment makes any blame for delays, for example, less easy to identify.
The biopsy isn't always accurate, mine was upgraded after the operation, and that's not uncommon. So the final treatment is a bigger factor.
Thanks for coming on here. I guess you're in Germany and it would be interesting to know more about how treatment goes there if you wish to continue asking or writing progress.
I recognise your name is 'questions'.
All the best, Peter