I did see that, but the answer does not make sense. The PBX is definitely involved in the call, which can be proven by the network logs as well as the fact that it is mediating the connection of the call via the Rebound feature.
There is no technical reason that recording a call forwarded to mobile should not be possible. The PBX is right at the center of the the call.
The PBX is involved in the call as far a the SIP session goes, but the audio does not pass through the PBX in this case and it handled by the provider. That makes the recording technically impossible under this scenario. In a "ring my mobile simultaneously" case, the audio does pass through the PBX and hence can be recorded.
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