For anyone with the same problem as me, the correct name to address the iPad 2018 in a DefaultDeviceProfiles.ini is: “IPadPro2_129”.
[IPadPro2_129 DeviceProfile]
DeviceType=IOS
BaseProfileName=IOS
+CVars=r.MobileContentScaleFactor=3
This is what worked for me.
I found it out by using a “Get Active Device Profile Name” pin, and printed it on my iPad.
I hope this helps anyone in the future!
ND