I wouldn't put any money on 10 F... I have a Hirado that had some twig damage at 24 F.

Ten degrees would really be pushing it for Chandler Pummelo or most pummelos for that matter. I'm not suprised to see the Lowes tag have that info on it though. Often they don't seem to have all the facts straight on their plant descriptions.
There is one pummelo that has been known to survive 0 degrees and come back. The Tokyo Pummelo aka Hanna Pummelo was brought back from Japan in the early 1980's by Dr. Wayne Hanna (who incidentally will be hosting next years citrus expo) by way of seed. The mother plant was covered in snow & was full of fruit which caught his attention. He sent seed back to himself and planted it in his yard. Although a very vigorous grower it was set back some years ago after it froze back in 0 degree weather. It did make it through and has been producing fruit in the last 6 years or so. The fruit are large, dense, fairly seedy, and pretty tart. If you were able to overwinter the fruit somehow you might get a better tasting fruit. They would make a decent pummelo-aid with some sugar if you had to harvest early due to an upcoming freeze.

G, Pummelo do not come true from seed. Any seed produced plant will not be like the parent in quality or taste.

Of course & yes indeed -not true from seed but the seedling plant he grew still retained the cold hardy qualities of the parent plant and may even be more so. I may add that the zero degree temperatures this plant survived was in Georgia & the fruit I tasted was from this tree not in Tokyo, to clarify.

At one time there were several trees growing on the Texas A&M campus. I believe they were destroyed due to construction. There is one seedling from the original tree or trees growing in Port Neches TX.It has survived the freezes of 1983 and 1989 and produces fairly good fruit. It is not the quality of satsumas and usually has about 30 seed, not 40 , 50 or a hundred. Budwood was gave to me from a Texas A&M specialist, Dr. Arlie Powell. in 1989.