Wa alaykum assalaam wa rahmatullaahi wa barakaatuh,
This is not permissible, and the person who does that is in fact gambling with his religion, because misguidance is around him from two ways.
It´s either a doubt from the doubts of that innovator embeds in his heart. So it will embed in his heart until it misguides him, because the hearts are weak, and the doubts snatch you.
Or that you might find love in your heart for that innovator, until you reach a point where you do not reject any of his sayings, and the matter would be like the poet said:
If Hutham said something then believe her
For indeed the [correct] saying is what Hutham says
And specifically those who claim to be Salafis, because being deceived by those is more likely than others, as they wear the dress of the people of the truth, and speak with the words of the people of truth in most of their speech. So truth and falsehood would be mixed together for those who are not firm upon the Manhaj of the people of the truth and their creed. And as it was said: A Bid´ah of an innovator did not spread except because of the [portion of] truth that he has.
And the people of innovations spread their innovations in all types and chapters of knowledge, even in language, and if the innovator wanted to spread his Bi´dah through language lessons he would have done so.
Therefore, I advise you and advise all students of knowledge to take their knowledge from the pure sources of knowledge, which is full of pure and clear knowledge, because Allaah has bestowed us with the bounty of having pure scholars in all fields of the knowledge of Deen, so praise be to Allaah as we are not in need of the lessons of the people of innovation
And Allaah (the Most High the Exalted) is the one Who gives success and guidance to the right way. so I ask Him to make our hearts firm upon the truth until the Day we meet Him.