Look at it this way Institutional buyers were willing to pay...

Look at it this way Institutional buyers were willing to pay 5.20 for the measly 8% of stock not taken up. As it was a book build it shows that demand robust upto the theoretical price. Or there abouts. My guess is those who had bids below 5.20 and didn't receive any stock looking to add.

I do agree that issuing 36% of shares at such a significant discount will mean over over medium term there is selling pressure for that stock until management can demonstrate they have taken positive steps to turn the situation around.