Was Timit the fool also on the team?
If so, as far as I can see this is an intended mechanic and works as follows:
if timit is not on team -> revive all allies in one go
if timit is on the team and alive -> revive all allies (blocked by lydia)
if timit is on the team and is the only one dead -> revive timit (blocked by lydia)
if timit is on the team and is not the only one dead -> revive timit first (blocked by lydia) and then revive all other allies (not blocked by lydia as it already blocked timit's revive).
this seems to be intended as the interaction with timit is that he gets revived with full HP and full turn meter, whereas other allies are only revived with 50% hp and 50% turn meter, thus, the skill counts as two seperate revives if timit and at least one other ally is dead.