[jkyle]

Well, they can "compel" in the sense that they can demand the owner release it.

The owner can refuse and suffer the legal consequences.

In such a case, has there ever been a precedent of going to the safe manufacturer and compelling them to break into the safe? Have they ever then required all safe makers to make exploitable safes with master keys?

[lern_too_spel]

In the case where the safe maker has special ability to break the existing safe, there is plenty of precedent. Every application of the All Writs Act follows that analogy, including this San Bernardino case.