At the final cycle, teams can sign a player with less than high consideration. Before the final cycle, a team needs to be at high or greater to sign.
So basically, in the scenario you’re presenting, the player will not sign with anyone until at least one team with an open spot gets to high consideration, or higher; until the final cycle, at which point the player will choose among teams who have offered a scholarship and have an open spot, even if they are not at high consideration. That final cycle may not show the player as signed right after it runs. As with the previous version of the game, the final signees actually happen sometime after games are processed (I don’t remember exactly when). To your second question, the player will not go unsigned, provided at least one of those teams who have offered a scholarship actually have an open spot.