Q1: After the On Deletion effect of this card plays a tamer card, can this card be placed under that tamer in a "save" after "then"?
Yes, it can be placed.
Lv.4 Greymon BT19-020 U Champion | Virus | Dinosaur/Blue Flare <Rush> [On Deletion] If you have 1 or fewer Tamers, you may play 1 [Kiriha Aonuma] from your hand without paying the cost. Then, <Save>. --- Inherited: <Reboot> (This Digimon also unsuspends in your opponent's unsuspend phase.)
Lv.4 Greymon BT19-020 U Champion | Virus | Dinosaur/Blue Flare <Rush> [On Deletion] If you have 1 or fewer Tamers, you may play 1 [Kiriha Aonuma] from your hand without paying the cost. Then, <Save>. --- Inherited: <Reboot>.
Lv.4 グレイモン BT19-020 U 成熟期 | ウィルス種 | 恐竜型/ブルーフレア ≪速攻≫ 【消滅時】自分のテイマーが1体以下なら、自分の手札から、「蒼沼キリハ」1枚をコストを支払わずに登場できる。その後、≪セーブ≫。 --- Inherited: ≪再起動≫(このデジモンは相手のアクティブフェイズでもアクティブになる)