i wonder if harrow ever went back into the locked tomb. she went into it once and i dont really know enough about how blood wards work to know for sure what happened to the door afterwards. did the blood ward simply let her pass or did she actually unlock the door? did she merely get through the subsequent traps or did she disable them in the process?

just because harrow had the key (gaiusblood) doesnt mean that the door would let anyone else through, past or present. but i also think it would be interesting to think about what if the tomb was unlocked, properly, and if harrow would have ever gone back.