It was more efficient to blow up a real 747 than to use miniatures or CGI
A mothballed 747-100 might be worth almost nothing, literally cents on the dollar, especially as anything valuable will usually have been removed by various parties before it even hits the boneyards. And during the current situation where air cargo, the only viable use for even airworthy old 747s, is not growing I can see some broker selling a plane in the low single digit millions. An airworthy 747 will of course be worth more but the article doesn’t mention that and it seems unlikely.