Skimlinks - Blogger Affiliate

[PShez]

Just to give you a bit of background - we are going out of our way to get bloggers to talk about and link (we are not paying for them) to our products.  We recently noticed that a number of these bloggers have signed up to skimlinks and are using shortened URL's (fave.co/12345) and are no-following these (is this correct procedure?).

It's a little awkward, as it's devaluing our PR teams work, as we aren't able to see the sites generating revenue, GA simply shows the affiliate number (skimlinks) and that's it.

has anyone else had similar issues with skimlinks and if so how did you deal with them?  Are the links they are "hijacking" harmful to our site?