At this point, I think the only viable thing that can truly contain it is a reverse-time machine. Instead of speeding you either back into the past or present, it would just make a second for you last hundreds of years for your environment.
Essentially, lock the sucker up in statis. He would have no time to adapt and under centuries, surely, a better alternative would present itself or other, sufficiently lethal SCPs might show up.
I got the perfect plan!
Step 1: Wake SCP-239 up, tell her the plight of SCP-507 and manipulate her into wishing SCP-507 have some kind of wristwatch to control where he shifts through dimensions by voice. If it works, put her back to sleep.
Step 2: SCP-507, after gaining said wristwatch [SCP-507C], will shift to the Halo Universe with a group of soldiers and engineers, specifically on a Halo Installation.
Step 3: The Team will find way to remove a Forerunner Stasis Pod [SCP designation pending] and bring it back to SCP home reality.
Step 4: Team will then transport to Star Trek Universe and negotiate for a working Transporter, along with schematics.
Step 5: Modify Transporter, making it that anything going through the transporter as a matter stream will be stuck in the Transporter pattern buffer module ala Montgomery Scott's technique.
Step 6: After getting both devices to work, sedate SCP-682, put it into the Forerunner Stasis Pod and freeze him in temporal-stasis.
Step 7: Put the Pod into the modified Transporter as soon as possible and put the pod and SCP-682 into the Transporter buffer.
Step 8: Given that Transformer Buffers have only 420 seconds storage life before irreversible degradation, SCP-682 should be destroyed quickly enough, with two stasis effects preventing it from developing resistance.
Would this be crazy enough to work?