However, does anyone know how the law works with their bankruptcy because I actually owned the miner? Do they have to send it to me?
No, and no. You'll need to read your contract very carefully, as that plays a pivotal role. In colocation cases, the contract will often either specify that you can collect your hardware in the case of a dissolution of contract, or if you're unlucky.. nothing at all.
If you're not in a position to collect it, even though the hardware is yours, they're typically not under any obligation to send it to you and incur further costs, taking away from their creditors. However, they also tend to want to avoid further conflict and duress (they have your hardware, but they can't exactly just leave it sitting there, or move it to some warehouse with the expense of keeping track of it), so you should be able to work out having the hardware sent to you or to another location just to get it off of their list of headaches - if not at their expense, then at your expense (try to avoid that, though the contract may leave you no wiggle room there).
If you don't have a lawyer (or just don't want to pay for one), you can work with the trustee/liquidator (eventually) directly. In either case, you should start collecting all information you have - the contract, any details about your hardware, etc. and start reading through it.
