Just a thought if the handset doesn't allow input of the coordinates - if you have one or could find a gps unit may be worth testing?
https://www.teleskop-express.de/shop...obsonians.html
It will plug into the handset and then when you turn the goto dob it will say gps found and do its gps searching and then set the date/time and location details. You have to input the timezone and if its daylight saving.
It wouldn't be worth currently to buy one if you don't have one - it is to test.
I have one of those gps units i use with my synscan handset.