From what the leaky people told us, Mercury was dead against doing anymore which makes it seem like Konami would have had to do A LOT of persuading ($$$) to get them to do another. If LoS2 had been a huge success, sure, but it doesn't seem like it. Unless MS had a change of heart...
I do think LoS2 wasn't as much of a financial failure as it may seem - namely, since LoS was made on a low budget with low expectations (and far exceeded them) and LoS2 presumably had the same budget (same VAs plus richard madden pretty much), it shouldn't have lost Konami much and may even have been profitable. But still ehhhh. Who knows.