Personally, I would hang onto the 66 gal, and attempt to re-seal. You may find you can use it later! Maybe try re-filling after the repair in a location where the possible leakage won't cause harm though, just in case.
The hobby is addictive, as you probably already know...
Freezing of the silicone sounds like B.S. to me as well, personally. And if you caused a leak by moving it, it may well have leaked in the near future anyway. IMO
Good luck, a larger size tank was the way to go probably-BTW, that's a great looking stand, too!
