I guess one way would be:
Following a shot on goal, was the play stopped? From which you could very roughly deduce that: Per game,
Defense Face-offs / Allowed SOG = Rebound control %
Of course that is wildly unreliable (eg. stoppages due to puck in the audience, penalties, etc), and there's no way to tell which side the face-off is in (do they keep track of that?), but could be a basis for some sort of analysis. I guess at least you could remove the amount of penalties from the
Face-offs statistics.
But let's say, you can tell that there were 15 face-offs in the defence zone of Team A, and Team B had say 25 shots on goal. Then 15 / 25 = 0,6 = 60 %, so Team A's goalie controlled 60 % of the rebounds.
It's problematic if there are more face-offs than shots on goal, eg. 30 face-offs and 25 sog = 30/25 = 1,2 = 120 % rebound control
But not sure if there are more D-zone face-offs than SOGs in most games. From a quick look, there's an average of about 60 face-offs per game, but that doesn't tell which end. So if you guesstimate a 50/50 division between offensive and defensive face-offs, it's roughly about equal to average shots on goal per game.
Edit:
Hmm, actually here you can see current stats for O/D face-offs:
Team face-off stats- 2018-19 regular season - 2018 - defensive zone - Puckbase
Roughly 20 defensive face-offs on average, which tells there's usually less face-offs than SOG, which could make this a viable quick'n'dirty check for goalie rebound control?
This could be tested by watching a couple of games and comparing real rebound controls vs. the rough formula.