Segwit2x supporting miners will be "heavily influenced" in the next 90 days NOT to raise blocksize to 2 MB.
Some of them will not. Some of them will want to. The former will keep blocksize to 1 MB. The latter will join to mine the Bitcoin cash fork.
At the end of the year BCH fork will have about half of the BTC hashrate and half of the price.
In numbers it will look something like this:
5000 PH/s for BTC, 2500 PH/s for BCH
$3000 for BTC, $1500 for BCH.
my prediction a bit different from yours. bitcoin will stay at 5000 $ and BCH end up around 2000 or 1500 $. and if bch fluctuation same as before it will drop im afraid that would just happen like before.