Sugar is a preservative so if it look OK then it probably is.
Sugar is a preservative in the general sense that it binds with the water molecules, thus reducing the "free water" available and necessary for pathogenic organisms to grow.
Just cleaned out cupboards... WAAAYYYY in back were a few odd jars of pepper jellies and a cactus something like jam.....
No exp dates.
Chuck or ok?
That is waaaaay over my head, but I've kept jellies in the fridge for a few years. ( they get hidden sometimes). If no mold, (and there hasn't been) we eat.