Your XPro-C and X2T-C Godox trigger speakstriggers speak a different "language" than the radio receiver in the Canon 600EX-RT flash. You can't control the 600EX-RT directly via radio with a Godox trigger.
To control the 600EX-RT with your Godox triggerstransmitters you need a compatible Godox receiver attached to the hot foot of the Canon flash. For a long time, theThe only such receiver available wasis the X1R-C.
The new Godox X2T-C ishas a transceiverbluetooth receiver, but that can be usedis only for using select smartphones to control the X2T-C via the Godox app. It's not capable of acting as either a transmitter or receiver for other Godox triggers.
Be sure it is set to "receive" instead of "transmit" when attached to the hot foot of the Canon flash. It also needs to be on the same channel asnumbers on the XPro-C transmitter. If you want to control it independently ofand the Godox V860II-C, select a different group, but (or any X1R-C receiver you still needare using attached to be on the same channelanother flash) match. All wireless ID numbers should also match.¹
¹ You may need to turn wireless ID to "off" on all devices to get things to work with the V860II-C, which does not appear to support wireless ID.