Unfortunately, I can confirm that. AFAIK, there is no way to identify the touchscreen vendor from the outside. Mine is very difficult to use even at higher battery levels. The keyboard responds with up to four characters per touch, which makes it unusable for entering passwords.
I’d love to find some hidden switch to repair that. So far, I have used this documentation to play with parameters, but I guess the problem is one level below this layer of abstraction.