I doubt it's much of a backfire. Taylor is on the ballot but all he has to do is do nothing. No ads. No fundraising. No appearances. Refuse to debate. He won't attract many votes.
But by leaving Taylor on the ballot then Orman can still argue he's the independent in a three man race. Had Taylor been dropped then Roberts could have labeled him as the defacto Democrat. Now he'll continue to try and do that but it won't be as effective.
The extreme gyrations and contortions the Democrats are performing in their effort to get Taylor off the ballot would indicate otherwise.