Aphids? Virus? Something else? No visible pests, roots are fine🤷‍♀️

Pics 1&2 (Bronze Buddha) suddenly got these sticky sundew spots on the underside, and I immediately thought aphids. I can’t find any, tho. I checked with my loupe all over, checked the bark substrate, leaf joins, and nothing. I’ve had it in quarantine for weeks and it’s only gone a little yellow along the margin. Should I just spray in case?

Same story with the second one, pics 3-5, all of a sudden it got pits on the underside that turned yellow then brown and started showing on the top leaves. Again, no sign of pests I can see but it keeps getting worse. Could it be a virus? It was a mystery ID so I just want it to live to see the flowers!