The red color seems to scream 'BIRD POLLINATED!!!,' but I don't know how that would work. Is it just a fly or bee like most other slippers?

I would have to guess flies/hoverflies and or bees.

I have heard a tale of a scientist observing hummingbird visitation, but not proof that the hummingbird actually performed pollination...

Hummingbird is a possiblity. I have been to the rainforest of Costa Rica and I actually saw a couple of hummers buzzing around wild orchids.

I was told a hummingbird was seen hovering around a bessae flower in the jungles of Ecuador but the source was not too reliable. :rolleyes: