Yikes. This has the potential to seriously damage the reputation of Mozilla. I guess there are 3 possibilities:
Onerep isn't actually shady, but partnering with a company part of a conglomerate with companies directly opposing the stated goal isn't a good look either way
Onerep is shady and Mozilla failed to conduct the necessary research before partnering with them
Onerep is shady and Mozilla knew
In any case: Personally, I'll never not be grateful towards Mozilla for continuing to support and develop Firefox, which is quite literally the only relevant engine standing against the monopoly of chromium and all the bad that entails. But I trust other companies/initiatives/projects more when it comes to services other than the browser engine.