Disclaimer: I'm one of the devs of the platform so i'm a bit biased - but the process works well and is already used a lot, you can check all the loan requests available on the platform. Also if interest i can detail more how this interchain service works.
So you are one of the devs of Ethlend.io, as you say. Can you prove it?
Sure i can, whatever way you prefer. Shoot me an email to emilio******at*****ethlend.io and i will reply back, or add me on twitter (@The3D_) linkedin (Emilio Frangella).
Also i will detail a little how this application allows you to put real BTC as collateral and receive a loan in ETH or ERC20 - basically the previous versions of ETHLend only allowed loans within currencies on the ethereum blockchain (so you could pledge ETH/ERC20 and get an ETH/ERC20 loan). With the latest and current version, we developed a 2-out-of-3 multising arbiter for bitcoin which allows interaction with the BTC blockchain. Basically what happens is you can go on the platform, ask for a loan, when the loan is granted a smart contract is instantiated on the ETH Blockchain and a multisig between us (ETHLend), the borrower and the lender is created. So the agreement is executed in a decentralized way on the ethereum blockchain, and there is an oracle (that is handled in a centralized way by ETHLend at the moment) that acts as an arbiter between the lender and the borrower to handle the collateral. So if for example the loan is repaid the borrower and the oracle will both sign the tx to move the collateral back to the borrower, if the borrower does not repay, the arbiter and the lender sign a tx to give the collateral to the lender. So ETHLend alone cannot do anything with the collateral, as you cannot sign transactions with only one key in a 2 out of 3 multisigs.