brown leaf

My roth seedling’s oldest leaf browned, which is concerning to me since it’s a young plant. Is this normal or is there something wrong? I also attached photos of what I think is mesophyll collapse, but I welcome ya’ll’s opinions. I really want this guy to succeed.

I had a multifloral Paph hybrid arrive last week. It was in transit for about 6 days, so I’m worried about. It had one large leaf on its oldest growth brown, so I cut it off, however now an old leaf on its flowering growth is browning too. The other leaf tips of this flowering growth are...