Allium Remoulade's Links
Allium didn't view Isabelle as especially notable. He was vaguely aware that she was friends with Ollie, but didn't hold any strong feelings prior to their scuffle. He doesn't understand what she sees in Ollie, given what he knows about him.
Isabelle can't see how anyone would attempt such a horrible thing on their own sibling. She believes that Allium doesn't understand what he'd be missing if Ollie were gone - and fully regrets that she's put Ollie into a situation like this because of Allium's selfishness.
Allium has always been jealous of Ollie, who has had their father's approval despite Allium putting in the hard work. When brought to OFFLINE, the game's twisted rules was enough to push him into wanting to take Ollie out of the picture - only to fail and be killed himself.
Olive's view of Allium is... complicated. Though a piece of them still believes that Allium cared for him, Olive has come to terms with the fact that he was overly dependant on him, and that Allium was definitely jealous of how favored Olive was. Though Olive recognizes that these events caused Allium's decision to try and murder them, their interactions with their friends has prevented that guilt from consuming them and, with time, have allowed them to take the first steps towards moving past those events.