No. There are two reasons for this:
1. An SZ1RV1202 potentiometer requires a 10.5 mm drill hole for installation, whereas the enclosure has a 22.2 mm drill hole
2. The intermediate metal contact fixing plate does not leave enough space below the front panel for the potentiometer body
A possible solution is to use the XACB or XACM boxes with XB5 range potentiometers and potentiometer heads. See attached catalogue page for potentiometer options (taken from Harmony XB5 Catalogue November 2019).
However, these don't have the same mechanical shock features as the XACA + XB2 range, and there is a potential that the rear portion of the potentiometer may detatch from the head if the unit is bashed or dropped. Please factor this into whether or not this is a solution in your instance.
Failing this, the only solution would be to use a fixed control box instead e.g. XALD01, along with an XB5 range potentiometer.