It’s not really because it fell over. It’s because it wasn’t supposed to fall over. Consumable launch materials don’t contend with this because failure to return is a success. This is a failure. This must be learned from and fought against/prevented going forward.
One thing I can think of is an overzealous corporate security solution blocking or holding back your email purely for having an attachment, or because it misunderstands/presumes the cipher-looking text file to be an attempt to bypass filtering.
Other than that might be curious questions from curious receivers of the key/file they may not understand, and will not be expecting. (“What’s this for? Is this part of the contract documents? Oh well, I’ll forward it to the client anyway”)
Other than that it’s a public key, go for it. Hard (for me anyway) to decide to post them to public keychains when the bot-nets read them for spam, so this might be the next best thing?