Awoniyi, a late substitute for Ibrahim Sangare on Sunday, received lengthy treatment on the pitch.
Elanga was in an offside position when he collected the ball but the assistant referee did not raise their flag until after Awoniyi’s collision.
When an immediate goalscoring opportunity is likely to occur, assistant referees are told to keep their flag down until the passage of play is complete.
If a goal is scored, the incident can then be reviewed by the video assistant referee (VAR).
Although this allows goals to be scored, critics say the protocol needlessly endangers players.
Forest owner Evangelos Marinakis took to the field after the game to express his concern to manager Nuno Espirito Santo over how Awoniyi’s injury was handled.
Marinakis is being kept updated on the forward’s condition.
On Tuesday Forest said Awoniyi’s injury was «a powerful reminder of the physical risks in the game and why a player’s health and wellbeing must always come first».
