Microsoft graph call transfer using specified resource account / number - microsoft-graph-api

Question

Using a Microsoft Teams bot and the graph call create api, I am able to call myself (as operator) and transfer the call to an outbound PTSN number. When the bot calls myself, I can confirm it calls using the specified resource account and the associated phone number. However, when transferring this call to the PTSN number, the receiving PTSN number sees my number instead of the bot's resource account number.
Is there a way to specify which resource account to use when transferring the call to the PTSN number? I have searched the docs, but could not find any solution.
To make it clear:
Bot calls operator using resource account (e.g. [phone]).
Operator takes the call, the bot receives the established state update and starts the transfer to the PTSN number (e.g. [phone])
The receiver of the transfer now sees the number of the person being transferred. I would like the receiver to see the number of the bot ([phone] in this example).
Request payload used to transfer:
{
"transferTarget": {
"endpointType": "default",
"identity": {
"phone": {
"id": [PTSN NUMBER OF RECEIVER]
}
},
},
"transferee": {
"identity": {
"user": {
"id": [ID OF OPERATOR],
"tenantId": [OPERATOR TENANT ID]
}
}
}
}