I just realized that I never really put much thought into what Julius was planning to do with Elle. Nothing good, probably... There's a chance he was gonna try to complete the trial himself using her to save Ludger from having to go through the trial, or perhaps he didn't care about the trial at all and was simply going to kill her. After all he never was going after the waymarkers for himself, the first one he stole just to lure Ludger out (or at least guarantee Ludger would have to run into him eventually since spirius would no doubt want Ludger to go after him), and then after that he wasn't really 'seeking' waymarkers so much as being a diversion for Chronos. Either way it's unlikely that he would have wanted to protect Elle from spirius, I mean if that were the case, why not let Ludger in on it? He most likely wanted to separate her from him to prove to Bakur that Ludger was not the key and hopefully dissipate Bakur's interest in him. And without his watch, Ludger wouldn't be able to use his chromatus, and not only would he not be able to work as an agent anymore, but he'd likely be scrapped as a candidate for the soul bridge. To Julius, Elle was most likely just another threat to his brother. It wasn't until Julius saw just how much Elle meant to Ludger that he started to show any compassion towards her, and decided to help Ludger make it to Canaan by keeping Chronos at bay.