I leave it to others (if they wish) to comment on the breeder and MKA ...
It is generally recommended that dogs suffering from cryptorchidism (whether unilateral or bilateral) undergo surgery to remove the undescended testicle/s. For reasons, just do a search on the internet ... and you will find lots of articles on the subject.
The procedure is not complicated and the surgery fairly common place ... While there is risk in any form of surgery, the risk is minimal and your pup should be fine ... so not to worry too much.
Just find yourself a good vet with experience, to perform the surgery.
Just one thought though ... you might like to wait until your dog is about a year old before going for surgery ... It is possible for undecended testicles to "suddenly" descend when a dog hits maturity ... Undescended testicles (as I understand the condition) is not immediately life threatening in any way ... And it may be good to just wait awhile and see if the dog's condition reverts to normal all by itself ... Check with a good vet.