The last time i remember Frankfurt priced Ekitike £75m. That's crazy his price already increased £10m. If i were Liverpool, i'd rather sign proven PL striker with such amounts of money. £85m ain't small money, and must be used carefully when signing a new striker.
They should have learned how flop Nunez was. The better they to buy PL proven to ensure their money worth with the player they sign.
Nevertheless, Isaak and Ekitike are not comparable since Isaak's stats was on PL, while Ekitike was on Bundesliga. We know how PL much more difficult than Bundesliga.