If they were serious about the investigation they'd probably get a sneak and peak warrant to install a keylogger/etc. (either electronically or physically) instead of just a smash and grab. That way they'd have some good trial evidence, because as you say relying on forensics for computer crime is quite dicey - something the bureau is all too familiar with. If they can beat the system electronically this also gives them a chance to see whether there is anything that'd make a quick seizure worth it.

The law enforcement exposure they just did undoubtedly made it much easier to get warrants or FISA approval if they did have some targets.