Radagast suspected nothing...
Saruman was the head of the Council, why would it be suspicious for him to summon
Gandalf to him, in time of crisis such as it was? It was Radagast that allowed Gandalf to escape, as well, though indirectly...since Gandalf asked him to spread the word amongst all the
birds and beasts, to keep an eye out for him...and he did so, that is how
Gwaihir found Gandalf at
Orthanc. Radagast simply 'abandoned' the quest...or perhaps he had a different purpose all together, since
Tolkien's notes indicated he was sent on
Yavanna's behalf...which then explains why he was more enamoured of the wilderness, and the birds and the beasts of
Middle Earth, than with the people.
What book or writing has Tolkien's speculation about the
blue wizards and 'magic cults'? In UT, it simply states that they went into
the east, with Saruman, when they first arrived, but did not come back. Also, it declares that
Orome chose Allatar, and that Allatar took
Pallando as a friend. And perhaps they were destined to go to the further parts of Middle Earth and stay there, since Orome had the greatest knowledge of those areas. I would assume that, had they been seduced by
Sauron to serve him, he would have been much more powerful. Or perhaps their service was just what made Sauron's 'arm' so long...controlling tribes of
Easterlings and
Southrons, and other
men from farther parts of the world. Though it is said that those
peoples had been under his sway since the
second age, when he first began his
wars with the exiles from
Numenor.
I wonder what the significance is of having five
Istari...when two of them are never mentioned except to note that there were five all together.