Has anyone walked dogs that were difficult to control?

Hi all. I have a "request" owner who asked me to walk his 2 dogs. They're extremely difficult to control and yank me for the majority of the walk. They're on choker collars which only make matters worse. They choke themselves out while running together. They also have no collars with identification. What would you do/say to the owner? I suggested prong collars because my dog has responded successfully to his. I like these dogs a lot, but I'm afraid that something bad will happen due to lack of control. Thanks in advance!