With the score at 2-2 with nine minutes remaining Toti thought he had scored the winner, only for the visitors’ wild celebrations to be cut short by an offside flag.
The decision was checked but the on-field call could not be overruled due, according to broadcaster ITV, to there not being the correct camera angle.
At the time Lopetegui was absolutely convinced it was a goal, having watched it back on a monitor in the dugout, and stood on the touchline making the VAR TV symbol.
“We can’t do anything. We have talked with the referee. He was very quiet but he hears us,” he said.
“It was a pity because today there was VAR. He tried to explain but it wasn’t very clear but, of course more or less, I will show him I think the goal is valid (from) our tactical camera. I have seen the replay.”
When told there had not been a suitable angle available for the video assistant referee Lopetegui added: “I didn’t know this. It was a pity for us.
“Today we are unlucky with the decision and unlucky that we have a lot of chances, enough to win the match.”
The former Spain coach, with a Carabao Cup quarter-final to come on Wednesday followed by a relegation six-pointer against West Ham, made nine changes but his side still performed better.
“I’m frustrated and disappointed,” he said.
“The reaction is a little bit disappointed because in one way I am very proud of the players, they have deserved much more today.
“It was a pity that against a fantastic team they had a lot of chances and scored a third goal and I have to accept (the decision) but it is not offside.”
For Liverpool manager Jurgen Klopp this was another in a growing list of frustrating performances.
After Alisson Becker’s mistake had handed Goncalo Guedes the opening goal his side went ahead through two brilliantly-taken goals from Darwin Nunez and Mohamed Salah but could not prevent Hwang Hee-Chan from forcing the equaliser.
He admitted they deserved no more than a replay at Molineux.
“We deserve not more than a draw. I don’t think we should have them (replays) but I knew we still have them,” he said.
“Wolves are more happy than we are but we will be happy enough to give it a go.”