Distributions to paid in Capital (DPI) measures the ratio of money distributed by a fund against the total amount of money paid into the fund. At the start of the investment, this ratio will be zero, and will begin to increase as distributions are paid out. When the DPI is equal to one, the fund has broken even, as money paid in is equal to money distributed, and any number above this indicates that the fund has paid out more than has been paid in.
Money on Money Multiple (MoM) is the amount of money returned divided by the amount invested for that particular investment.
To me this sounds like the same thing, unless we refer to the cumulative DPI or DPI(holding period) as the MoM?