Surgeons cut off hearts and livers and implant them to completely different persons. They are using special drugs to prevent tissue rejection.
Even accidentally cut off hands are sewn back wich are able regain their functionality in most part.
So why testicles can't be sewn back later? If freezing is not possibility, it is still possible to keep them alive with artificial bloodsupply, as they do with braindead people.
Erikboy