So storage seal when they fail cause there contents to vanish into nothing? Or are they assume they broke during the fire and ejected into the fire? The mention of damaging the seal implies the first but also raises interesting question about the limits of storage seal. Could you use a deliberately damaged seal to destroy evidence or a body? And if you can seal someone even briefly can you use it to instant kill them.
What happens when you damage a storage seal will vary greatly with the seal, what's sealed within it, and how it was damaged.
At a basic level, some seals the items become unrecoverable. Others the failure results in expelling the contents. In a fire it probably doesn't matter which unless you're
really good at identifying remains in the ashes.
In my interpretation for this story, anything with sufficient chakra inside causes most storage seal variants to expel their contents upon being damaged because the chakra resists being "lost" like that. This goes double for seals holding living things that generate their own chakra, except that the living thing's chakra immediately starts attacking the seal from the inside. You need a specially designed seal to prevent that, either designed to weather the attack of chakra in some fashion or designed to fail
specifically to prevent the sealed-away contents from returning, and even that won't stop some things. Like the tailed beasts before the Tome got involved.
"Lost" items from a damaged seal that
didn't expel its contents, techniques that seem to permanently remove items from existence, and other such events eventually feed into the world's chakra and serve as the raw materials for when the opposite happens and chakra
creates matter instead.
And thus yet again Orochimaru proves that his brain works better than his so-called 'colleagues'.
He's smart enough to not want to be in the organization, to realize that at the time he was approached he wasn't actually able to say "no", and to know that so long as he plays along he gets the organization's backing in several ways.
As soon as he decides that staying a member is worse than leaving he's going to leave, and feels that they can't stop him anymore.