Rebar is soft enough that, if you have a good vise and a big ball peen hammer, you can flatten out one end so a properly sized fender washer won’t get over it. You can the drill your fender washers near one edge and “s” hook your chain (which you should shorten to 6”) to the fender washer. Drop a stake, so headed, though the washer and there you are.
Personally, I gave up rebar for cable “stakes” a long time ago. They’re less weight and way more secure. A big northeastern coyote can rear up high enough and strong enough to pull a stake unless it’s extra long, and sometimes you can’t get an extra long stake in far enough in rocky dirt. If you have to angle it, you’ve effectively reduced the length and made a pull out possible. If you double stake, you’ve lost the swiveling capability. Also, with a cable, if some dirt bag steals your catch, at least they won’t get your trap unless they’re carrying cable cutters.
