The view of Ibn Taymiyyah, which you referred to is spoken about in the first link (S. M. Darsh).
To put it in the correct perspective, Ibn Taymiyyah states:
To make that which Satan has proposed a temptation for those in whose hearts is a disease, and those whose hearts are hardened, could happen only if Satan's spurious line were brought out into the open to be heard by people, not something hidden, in the soul. The temptation which happens as a result of this kind of rectification, is like that which happens as a result of this kind of change. Rectification of what has been uttered loudly proves more strongly the truthfulness and self-denial of the Messenger (SAW) than any other measure. Indeed, if he uttered something and later ordered that it be rectified - both instructions being Allāh's - and he is believed, and if he says that the rectification is Allāh's true word, that it abrogates and utterance preceding it, and that that which has been rectified is not Allāh's true word, then this demonstrates that he accepts the truth and that he speaks the truth.
(Al-Fatawa, v 10, p. 292.)
This cannot all be the desire of the heart, which the Prophet did not utter. (Al-Fatawa, pp. 120-121.)
Hence, it is incorrect to say that Ibn Taymiyyah agreed with the story. He did NOT believe that Prophet Muhammad saws made this statement because of any personal desire, but he believed that it was a chance for the Prophet Muhammad saws to clearly refute the views of the pagans.
this is what Satan has slipped into their ear, and not what the Prophet actually uttered
And this was clarified when the prophet Muhammad saws refuted their views on it immediately.
Hence, even Ibn Taymiyyah does not agree with the story as it has been presented (by the enemies of Islam). He believed that Satan had no influence on the Prophet Muhammad saws.
For more detailed information please read the following article which discusses the issue in great detail:
http://www.bismikaallahuma.org/Polemics/darsh.htm
I hope that answers your questions. The story is unanimously rejected as a forgery, but a small group of scholars believed in a seemingly similar account, which still had no theological iimplications.
And I should also clarify that the point the enemies of Islam are attempting to make is that these whispers of satan actually were part of the Qur'an for some time, and that they may reflect other satanic inspirations in the Qur'an.
Such a notion is clearly false since the Qur'an is vehemtly opposed to Satan and warns its followers against him:
35:6 Verily Satan is an enemy to you: so treat him as an enemy. He only invites his adherents, that they may become Companions of the Blazing Fire. 