TL;DR: In both canons we have no explicit example of this happening to anyone else. In A Song of Ice and Fire we don't even have enough information to infer what happened to the two examples we have never mind anyone else. For Game of Thrones we can speculate this has happened to others based on evidence but we can't know for certain.
A Song of Ice and Fire
Like Benjen in Game of Thrones Coldhands appears to be a pawn of the Three-eyed crow. The ravens are his eyes and ears and he seems to implicitly confirm it with a conversation with Meera.
From a nearby oak a raven quorked, and Bran heard the sound of wings as another of the big black birds flapped down to land beside it. By day only half a dozen ravens stayed with them, flitting from tree to tree or riding on the antlers of the elk. The rest of the murder flew ahead or lingered behind. But when the sun sank low they would return, descending from the sky on night-black wings until every branch of every tree was thick with them for yards around. Some would fly to the ranger and mutter at him, and it seemed to Bran that he understood their quorks and squawks. They are his eyes and ears. They scout for him, and whisper to him of dangers ahead and behind.
[...]
Meera's gloved hand tightened around the shaft of her frog spear. "Who sent you? Who is this three-eyed crow?"
"A friend. Dreamer, wizard, call him what you will. The last greenseer." The longhall's wooden door banged open. Outside, the night wind howled, bleak and black. The trees were full of ravens, screaming. Coldhands did not move.
A Dance with Dragons, Bran I
This would imply he is not the first tool of the Three-eyed crow and he won't be the last and so it is likely others have been saved in the same way.
Note, however, that the origin of the Others in the books has not yet been stated and so we have no evidence that the Others were created by the Children never mind how that process took place. We are told that they are "a different sort of life" and so it's quite possible they weren't created by the Children at all.
[the Others] are strange, beautiful… think, oh… the Sidhe made of ice, something like that… a different sort of life… inhuman, elegant, dangerous.
A Game of Thrones: The Graphic Novel, Volume 1
Game of Thrones
Unclear but likely
TL;DR: There is no explicit example of someone else as of yet but evidence suggests there may have been others.
The wording around how the Night King was created leads us to believe the Children may have created more White Walkers around the time they created him.
BRAN: It was you. You made the White Walkers.
LEAF: We were at war. We were being slaughtered. Our sacred trees cut down. We needed to defend ourselves.
BRAN: From whom?
LEAF: From you. From men.
Game of Thrones, Season 6 Episode 5, "The Door"
Notice that Bran uses the plural "White Walkers" and Leaf neither denies nor confirms that they did create multiple. However, this isn't anything explicit as we know the Night King can create more White Crawlers Walkers and so they may have only made the Night King still.
However, if we couple this with how Benjen was Saved we can assume more people have had dragonglass plunged into their hearts. Benjen was saved from turning into a wight by the Children of the Forest who then used him as a tool for their purposes beyond the Wall.
MEERA: Why did you help us?
RIDER: The Three-Eyed Raven sent for me.
MEERA: The Three-Eyed Raven’s dead.
RIDER: Now he lives again.
RIDER (to BRAN): When I last saw you, you were a boy. A fearless boy. Loved to climb the castle walls, frighten his mother.
BRAN: Who are you?
BRAN: Uncle Benjen. The last letter Jon wrote me said you had been lost beyond the Wall.
BENJEN: I led a ranging party deep into the North to find White Walkers. They found us. A white walker stabbed me in the gut with a sword of ice. Left me there to die. To turn. The Children found me. Stopped the walker’s magic from taking hold.
BRAN: How?
BENJEN: The same way they made the Walkers in the first place. You saw it yourself.
BRAN: Dragonglass. A shard of dragonglass plunged into your heart.
BENJEN: You are the Three-Eyed Raven now.
Game of Thrones, Season 6 Episode 6, "Blood of My Blood"
Notice here how Benjen mentions he essentially "works" for the Three-eyed Raven and so it is likely that the Children have created multiple pawns in their time for him especially considering the number of Free Folk who have been getting killed in recent times.
