The Will and Charisma of the scorpion were so low that had Sylas used <Astral Bind> from the start, he would have won immediately. Its average was only 45, while Sylas' was 180. That meant that Sylas could freeze it for a full half minute with just 0.5 Aether Units expended. If he chose to splurge on Aether, he could have kept it frozen in place for minutes with ease. The only way out for the scorpion would be to have a skill that countered his binding, something it clearly hadn't had.
But Sylas wasn't happy.
'Stupid on my part. I saw its stats, so I should have taken advantage of the weakness. If it had a Skill to counter, it would be better to find out sooner rather than later.'
He had wasted Aether on <Solidify > when if he cast <Astral Bind> first, it would have all been over almost instantly.