A good vetenary for my dog in Cologne?

I need a recommended clinic/doctor for my dog. She is 14 yrs and lately developed pain in the right front leg and could not walk anymore. We checked with three doctors who prescribed pain/ anti - inflamatory pills without detecting the cause of teh problem. Meanwhile she is getting worse and the kidneys became affected because of the pills. The doctor is keeping her over the we to give her perfusion for stabilizing her condition. Only on Monday the chief doctor of the clinic will have a look at the situation and then will do a CT to detect the cause of the pain. This is extremely expensive and is not relevant if the injury is not in the bones. I have suggested that they go first for a simplier investigation (ultraschale) ) which could shouw th emodification of the tissue, but the procedure is to do the most expensive one and then, if necessary the cheaper one(!?) I love my dog and I am worried about her condition. I do whatever is needed to help her get better, but I do not know to what extended the vetenaries are treating the animals with dedication or are chasing the money. If you know a good clinic/ vetenary in Cologne area, please let me know, time is passing quickly and I have to take a quick decission about my dog.

Thank you.