I'm not sure that I understand, where is the risk exactly?
You really don't see the risk? DRK is currently on a downtrend. What you're offering is only 20% higher than repayment. There is a very real chance that DRK can plummet over 20% of its current value over this 30-day time period.
As I said, I'll submit additional collateral if needed! Isn't this enough? Anyway, now I'm offering 150% collateral. Escrow is mandatory, though.