If you look back historically, you will see LINE and LNCO prices diverge in BOTH directions. In fact, I've seen LNCO almost $2 a share more than LINE with no real explanation. Just run a historical plot of these two stocks and you will see what I mean. I've traded these two stocks against each other and never lost money, selling the higher priced one and buying the lower priced one on the same day. Simply be patient and the stock prices will converge.
Ex-Div has little to do with price movement. Look at the NAV. Its 17.25, .11 below closing price of 17.36. MORL actually closed above its intrinsic value. Simply the action of the stocks in the index which are getting pummeled by the market because of interest rates rising.