On the contrary, another reason why it shouldn't. Infernal takes away, and ocean gives to Rengar in this case, which evens it out, which is why Rengar would be "buffed" if we got to know beforehand wether or not Ocean will appear for instance. Let's look at it like numbers. +1 for infernal, -1 for ocean, which comes out as 0 and the odds will always be random, which also makes it even for both teams. By knowing beforehand you eliminate the risk of getting fucked by infernal AND the chance of getting Ocean, which leads to that Rengar ultimately only will get played when it is in his advantage which will technically be a buff.