Based on the existence of another very similar published sword, we can conclude that this is not a one off creation, but rather a type that existed somewhere in the Sahel in the 19th century. Hales pictured his sword in a group of kaskaras, probably because of the blade, and so both of the swords we know like this have kaskara blades.
The style of the chape is Hausa, but it was not limited to just the Hausa states, as we see it on takoubas and telek daggers all the way from Bida to Adamawa and what is Northern Cameroon today. I have a similar chape on a wide bladed takouba, which I posted for comparison to other Northern Cameroon swords in this thread:
https://vikingsword.com/vb/showthread.php?t=24269
Adamawa and the Mandara Mountains are not that far from Lake Chad, and the area was part of Kanem Bornu at various times, with very strong Kanuri influence even after the Fulani jihad. I am not trying to prove that the sword itself is Kanuri, just pointing out that it did not need to travel all the way to Kano to get its current scabbard.
The hilt has the construction of takouba hilts rather than kaskara ones, but the choice of material is also important. Silver is almost never found on takouba hilts and very common on kaskaras, as Ed Hunley has demonstrated.
It appears therefore that these swords are the result of mixed influence, and therefore most likely from an area where takoubas and kaskaras were both used to some extent.