I don't know about it.
But it could be possible. Congress is not an angel too. So Digvijay may have no answers for this question where his party is indirectly questioned.
But here's what SIT report says:
In a positive note, given the inflamed situation in the state, SIT Chairman Raghavan records that the state government had alerted army authorities on a possible need for their assistance on 27 February itself. Modi had also called Union Home Minister LK Advani about the deteriorating law and order situation. This was followed by a fax message on 28 February 2002 to the Centre. Army columns started arriving in Ahmedabad during the intervening night of 28 February-1 March. Raghavan concludes that “it is clearly established that there was no slackness on the part of the state government in summoning the army.”
However, once the army had arrived, it needed logistic support. The Modi administration could arrange all of this only by 2.30 pm on the afternoon of 1 March. At Godhra, this took up to the afternoon of 2 March. By then, a lot of the horror had already struck. The SIT report records this slackness in deploying the army, but has chosen not to comment on it.
http://archive.tehelka.com/story_main48.asp?filename=Ne120211coverstory.asp
Modi called upon the army on 27th itself. This is a fact too. Its also alleged that he had given people 3 days to do whatever they want after which he has to control the situation. Controlling the situation is tough so he needed all the help he can.