do you think they plagiarized/copied To The Grave - Bea Miller? what are your opinions? We All Lie sounds way better to me though (lyrics/music)

no, I don’t think so but the backtrack and beat pattern sound similar. As for the melody, they’re not rlly alike.

It will be impossible to win a plagiarism lawsuit, that's for sure!
The feeling is the same, singer's voice, echo. The chord grid is different from the start, on the second chord. The third chord is the same however.
There are many similarities, melody, rif rhythm on the eighth notes. But the melody is actually different. Besides I find both versions interesting. A bit like variations on the same type of song.
It's possible that a producer said to the composer "I want something that has this kind of feeling", for example. Or maybe it's just a reminiscence of the composer. If we study the question, we'll certainly find other songs that have this feeling. It's pretty common in pop. There are only 3 chords here in a 4 beat bar (with a transition chord on the last eighth note for the drama, and several transition notes for Bea Miller).
Even the drama songs often have the same feeling between them, sometimes almost the same chord grid, and harmonic resolutions far too standard and flat.