Jabber, I believe you can freeze it, after all, we can buy all kinds of frozen potato products. However, I am not sure that the texture of the potato will be exactly the same.
Here's what the Idaho Potato Board has to say about it:
https://idahopotato.com/dr-potato/165 In short, they do not recommend freezing the prepared salad, but if you've boiled too many potatoes, those you can freeze.