Webb has been involved in a few debatable decisions recently and this is another to add to the list.
Hull's draw means Newcastle are back in the relegation places that they climbed out of last Monday and now means they must better the Tigers' result next Sunday to avoid the drop.
Newcastle are at Aston Villa while Hull entertain what is certain to weakened side from champions Manchester United.
Webb courted further controversy for disallowing what appeared a perfectly finished equaliser from Mark Viduka and the official then reduced Newcastle to ten men after dismissing central defender Sebastien Bassong for hauling down Kamara.
And a question ringing around St James' Park was, has Michael Owen played his last game for Newcastle?
The club skipper was nowhere to be seen against Fulham, with the official line being that the striker was missing having suffered a groin strain in training on Friday.
The woodwork came to Fulham's rescue on the quarter hour when Kevin Nolan and Obafemi Martins swapped passes only for the Nigerian to see his effort canon of the upright.
Viduka then rose well to power a header wide much to the relief of his former Middlesbrough team-mate and goalkeeper Mark Schwarzer.
St James' Park was stunned into silence four minutes before the break when Fulham grabbed their controversial lead and ultimately the winning goal.
Erik Nevland appeared to be offside but was allowed to continue his on the right with Damien Duff hopelessly out of position.
Nevland charged into the area before sliding a pass perfectly for Kamara, who had time to pick his spot and ram in his third goal in the last two games.
United started the second half with more purpose and Martins rifled a half-chance wide.
With 50 minutes gone, Nolan got on the end of a Danny Guthrie free-kick to produce a goalline clearance and corner.
From the flag-kick, Viduka glanced the ball into the net only for referee Webb to disallow it.
Newcastle's cause was thrown into turmoil on the hour mark when they were reduced to ten men with Bassong shown a straight red card when as last man he hauled down Kamara.
A man short, Newcastle were woefully devoid of ideas and they crowd lacked its usual enthusiasm and encouragement.
And it was Fulham who came the closest to doubling their tally when a Nevland shot stung the hands of Steve Harper as he turned it over the bar.
Martins almost grabbed an equaliser with a solo run that Schwarzer could only parry goalwards and Brede Hangeland got the ball clear.
Newcastle then almost grabbed a dramatic stoppage-time equaliser when substitute Andy Carroll headed on a Harper free-kick and the lunging Butt's effort was clawed out by Schwarzer at full stretch.