Looking at the stats backs this up a little - Kulak-Petry only had 4 minutes this season vs Geno (which in itself maybe says everything we need to know about whether we even see this match-up) and gave away 2 high danger chances with none back. Did well against us other than that, but still ended up on the wrong side of the scoreboard.
Looking at Petry's match-ups this season - tbf, he's got a lot of high quality opposition among his most common match-ups (Kucherov & Point, Marner, Kuznetsov, Aho, Larkin, Pastrnak, Tkachuk minor, Ehlers) but he's not done great against those hard quality match-ups. V Bad possession stats against the Tampa Two, good against Marner, average vs Kutznetsov and Aho, v bad against Larkin, good against Pastrnak, bad against Tkachuk, v good against Ehlers... it's not a disreputable standard. Not amazing either.
Looking at who Petry faced vs us this season... lot of Simon and Letang time, went very well for him, lot of Blueger and Marino time, went badly for him, about 10 minutes of McCann and Hornqvist that weren't great possession wise, 9 minutes of Geno that went ill, 9 minutes of Sid that went great, his time against Rust was bad... these are tiny, tiny samples, but if I had to guess, they say Petry will say more Sid than Geno and could do well with it.
Meanwhile Weber played more against Geno than any other Penguin other than Letang and that includes the goalies.
So yeah. Expect Weber vs Malkin, Petry vs Sid.