Is the ascription of the poetic verse "Bishr has established control over Iraq" to Al-Akhtal correct?

This poetic verse, "Bishr has established himself over Iraq, without a sword or shed blood," is attributed to Al-Akhtal, but it has not been authenticated as his, nor is it found in his collected works. Leading linguists, such as Ibn Al-A'rabi, Al-Khalil, and Ibn Faris, have denied its authenticity, considering it fabricated.

Even if this verse were authentic, it is impermissible to use it as evidence that Allah's istiwa' (establishment) over the Throne means "seizing control" (istila'). This is because "seizing control" only describes someone who was previously weak or overcome and then gained power. Allah has always been in control and dominant over all His creation, and the Throne was never beyond His reach. This meaning implies that Allah was contending for His dominion, which is false. In the Arabic language, istiwa' means rising and elevation, as stated by Mujahid and others.