Fake bitcoin classic nodes would not be able to raise the percent of support since they aren't actual miners. At the end the amount of hashrates are mattering.
Hashers can throw their power behind a classic miner then later withdraw their hashing power.
What would be the sense of doing so? You can't send a reasonable amount of hashingpower to fake nodes just to try raising the hashrate, you would need to put real power into it. And you would only do this when you are sure that the fork wins. You can't fake hashrate like you seem to suggest.
I am not talking about "faking hashrate" I am talking about a planned attack with real hashrate.
The motivation for such an attack would be financial (i.e. spend your BTC twice or convert it to fiat twice if exchanges end up on different forks).