There is no such thing as a semi closed loop. when using servos, it is closed or it would not work.
The control can be any normal control, the duel loop is closed in the servo drive, there is nothing complex about doing this. and the extra cost is minimal, servo drives with duel feed back are common, and most manufacturer's have had them for many years.
Here is a link to one manufacture that has duel feed back servo drives. Yaskawa / Delta and most name brand servo drives, all have this duel feedback feature.
https://www.a-m-c.com/what-is-dual-l...-is-it-needed/