RNH this year is at 1.18 points/60 5 on 5. That's good for the #148 position among centers (minimum 200 minutes played)
per Natural Stat Trick. That's a bit more than mere "struggling" - that puts him below literally every single current CBJ center on the roster ("current", because Riley Nash was just traded and Foudy is in Cleveland). Boone Jenner has been a better 5on5 scorer. Kevin Stenlund has been a better 5on5 scorer. Mikhail Grigorenko has been a better 5on5 scorer. Mikko Kokiu was doing better than that before he decided he wasn't good enough and retired.
For 2019-2020, he did admittedly do much better, with 2.23 p/60 (
link). If we could be assured we were getting that RNH, that would be nice. Unfortunately, that seems to be the exception rather than the rule - for 2018-2019, he's back down to 1.75 p/60 5on5, good for #86 (
link), and stays pretty consistently below 2.0 p/60 5on5 the rest of the way back. 2.0 p/60, incidentally, is the usual threshold for top-6 center scoring, although this year has been a bit low in that regard.
Basically, with the exception of last year, RNH has been below average as a #2C in points production 5-on-5 throughout his career. And he just had a peak year at the age many forwards tend to peak, and is suddenly doing
much worse. I mean, it's probable that this year is an outlier, but between that and his looking for his next big contract... there's legit concerns.