I love it when the actual explanation is actually just really easyThe GL brainrot goes deep. But you're right, this ain't a GL. And I'm saying this as someone who enjoys GL from time to time.
There wasn't even anything romantic going on between them here, everything that happened can be sufficiently explained by them being best friends. Crying for the death of your best friend isn't some gay thing.
...but the author tagged this on Twitter with 百合 (yuri) so in the end it's a GL by technicality. 😔