Maybe the event got patched halfway or you have incredible luck or play 24/7 (and have more than average luck). With the stated formula and 1k stamina it takes about 70 tries (or a whole day and night without pause) to get a 50% chance to win 1 fight. Needles to say, I did not have that much luck (and could not play 24/7).
Do not bother with Lola, unless you unlock her completely (or was it patched?). And you should go as deep as you can, as fast as you can. No fake 10 min should yield 2.3, complete Sanshi (10min) and fill up Geeky till fake should yield another 0.9, complete Ice (10min) and fill up Dora should yield another 1.9, complete Dora (20min) yields 0.8 and fill up Frecly for another 2.7. For anothe 2.5 complete Cherry and fill up Pantress. Pantress, Lola and Frecly each take 40 min fake to complete for the next Girl. How deep you can go depends on money/skills and do not forget to factor in training time, the 10 hour filming being the major point in planning ahead. One might calculate a sweet spot for "active" clicking, but you will reach a point, where you just unlock your hit girl, send her for training and complete any other girls in the training time. After training you might want to unlock additional scenes you lacked money or skills and reset afterwards to unlock your hit girl anew.
If you are not on training you can reset. But you have to wait untill you unlock your hit girl again. Enemy gets changed by reset. But you have lower stamina.