Kind of embarrassing they had to go "oops, not yet." That it was typed up in a press release meant it went through all the channels of review - I'm assuming they even ran it by the league probably? I wonder with everyone working from home, if this just got missed. You could be cynical/or an optimist and see this as Jarmo trying to get him on the roster for any post-7/1 games the team plays lol.
Anyway, not all that excited with the signing. Jarmo loves him a Euro "reclamation" type project. He's brought a lot of guys over - Hannikainen, Kukan, Lilja, Melart, etc. Most don't pan out. This isn't a Panarin-type of signing from the KHL, Grigorenko already has NHL history and it's spotty at best.
That said, shouldn't be too hard for him to beat out Wennberg for a spot.