And here is the information that I get from Block.io when retrieving private keys for address 3CdYdQcc79QywRbZsAToKJx3AC83GGr1Ke :
* Address: 3CdYdQcc79QywRbZsAToKJx3AC83GGr1Ke
* Address Type: P2WSH-over-P2SH
* Required Signatures: 2
* Redeem Script: 2 *** 2 OP_CHECKMULTISIG
* Redeem Script Hex: ***
* Public Keys: ["***", "***"]
* Private Keys: ["***", "***"]
I tried to open MultiSig wallet in Electrum but failed, because I don't have xpubs or xprvs. I only have the above information from Block.io and from coinb.in.