Yes, I wouldn't expect the underside of the leaves to look damaged with either virus OR thrips. But, with the thrips, it will look like the top surface of the leaf has been scraped off. Mosaic damage will look more like a variegated leaf - i.e. the chlorosis will be through the depth of the leaf. However, with thrips, you will usually see excrement along with the scraping. From what I can see, I suspect your initial diagnosis is correct. With any leaf chlorosis (especially if there are distorted leaves) I think you are wise to err on the side of caution and pull the plants. The mosaics are really tough to clean up once you have them
To continue working on your remaining plants you should rinse your arms/hands with a mixture of skim milk diluted with water/milk at 5:1 and rinse between sections or individual plants. And, of course, avoid touching plants with clothes, watering wands, etc. This will help in the future spread of any virus.