Newest leaf from the "mama" plant.

Whole mama plant.

Thought I'd also said:

I'm leaning toward 'Prince of orange' but the leaves I see in others' pics are usually connected to the petiole at their base, as are the leaves on the cutting from the top pic above. I planted a bare section of stem and those leaves are all new from the past few months.

The more mature leaves in the last pic are much more heart-shaped. That pot has 2 original growth tips with hard woody stems of what I was told used to be a huge vine too big to take inside for winter. (You'd think the owner of a garden center would know to make a bunch of new plants from cuttings to have ready for sale in the spring...?) Also do not see any 'POO' plants with maroon/burgundy leaves, just orange or green.

Not sure if it's a species plant or a breeder's cultivar.

The leaves are very thick and smooth.

What about 'Black Cardinal', 'Red Emerald', 'Imperial red'? Are these all orange inside?

The pic marked newest leaf on mamma looks alot like black cardinal but the overall looks nothing like my black cardinal, but culture makes a big difference...

Thanks for the input. You're so right. It may take a few years until this plant gets back to looking "normal" from its' harrowing experience. I admit it's hard to keep it from getting sunburned and have let some of that happen.

Pic from this morning. I absolutely love this plant and check on it a few times a day.

The babies from stem cuttings are doing great! Quite a different, less heart-shape shape of the much smaller leaves.

Didn't think this one was going to make it, but it's impressing me. Doesn't seem to mind sharing space with way too many Begonia cuttings.