I don't know if AUs of this nature are allowed, but maybe?

Peggy was assumed to be dead and was captured and experimented on (and whatever else) by Hydra. It's up to you what happened to Bucky, maybe it's a complete switch and he went on to do great things and grow old, or maybe they were both captured and Winter Soldier-ized.

No particular preference on how trash is incorporated, I'm just interested to see what a writer would do with it!