I would use the tote. Rinse it well first. If you can run a new airstone and new airline into it that would be good. A filter that hasn't touched any tank with dying fish would be even better. Don't use any water from the suspect tanks - if you can acclimatize the fish in a third container, maybe a bucket, then good - but remember you're trying to eliminate the possibility of toxins that may have leached out into the water. So once you've done the acclimatization process, net him out and put him into completely clean water.
Then see how he does. If you haven't got a seeded filter, do daily water changes to make sure ammonia doesn't build up. Remove uneaten food immediately - if he doesn't eat within five minutes, take it out.
If you had fish dying in the quarantine tank, you should sterilize it before using it again. I would use dilute bleach, then rinse like crazy, then use extra dechlorinator. As an extra step, I like to let a suspect tank sit dry for at least a week, although honestly fresh 10% bleach kills nearly everything. I'd see if you can get your goldfish into the tote before doing all that; if it's the silicone, then you need to get him away from it ASAP.