"Unhealthy" is a pretty safe bet :-) Japanese maples should not have a cluster of dead foliage and branches in the midst of what appears to be normal, healthy looking foliage. I would have said it is showing normal, seasonal deterioration of the foliage but that is much more of an all over appearance rather than dead, dried foliage mixed in with almost unblemished, green leaves. That is more of a sign of some pathogenic issue causing branch die back.

The growing conditions look to be rather challenging and that could be part of the problem. The space appears to be too confining for normal growth, under the roof eaves is preventing natural rainfall and may also be restricting light. That could be why it is producing those long whippy shoots rather than more normal growth patterns.

You could take samples into your local extension service office for a diagnosis but I doubt even knowing for sure what is wrong with your tree is going to make it look better and appear healthy as it should, even if it were treatable (some common JM pathogens are not). Removing and replacing with something more suited to that specific location might be the best approach. And the Fatsia is a very good choice for that.

As for identifying what type of JM you have, virtually impossible to say with any assurance. There are countless cultivars that resemble yours, at least superficially, but nothing that would distinguish it specifically from all the others. And knowing exactly what kind you have is not going to contribute anything useful to its problems now or any care going forward - all types need the same care and are susceptible to similar problems.