Should I drill drainage holes on the bottom on this nursery pot? Only holes on side/bottom edge.

My FLF is suffering from what I think is root rot, so I plan to repot her. Just like the nursery pot I bought my FLF in (Costco), it only has these side/bottom edge drainage holes but none on the bottom. Is this okay to leave as-is or should I drill additional holes on the bottom as well? I plan on putting mesh screens over each drainage hole.

Also, I'm repotting in Fox Farm Ocean Forest with some perlite and orchid bark. Any recommendations on a good soil mixture ratio with these? Thank you!