There was a hotline AND a website. You're conflating the two. About the website, Biden said, "go to IWILLVOTE.com to make a plan exactly how you’re going to vote, where you’re going to vote, when you’re going to vote."
About the hotline, he said, "What the president is trying to do is discourage people from voting by implying that their vote won’t be counted, it can’t be counted, we’re going to challenge it and all these things. If enough people vote, it’s going to overwhelm the system. You see what’s happening now, you guys know it as well as I do, you see the long, long lines and early voting. You see the millions of people who have already cast a ballot. And so, don’t be intimidated. If in fact you have any, any problem go to — and I don’t have the number but it’s 833-DEM-VOTE… Call that number. We have over a thousand lawyers, over a thousand of them, they’ll answer the phone, if you think there’s any challenge to your voting. Go to 833-DEM-VOTE, dial those letters on your phone. That will get you the assistance that we have already put in place."
The website was to help people vote. The hotline was legal assistance to counter voting roadblocks setup by Republicans.
But he never promoted either as an investigatory body to stop fraud.