Hi
if I understand correctly.
For point 1, if call arriving on a sip trunk into Genesys, which will be configured in the Admin Trunk section, you can edit the external trunk and enable "User to User Information" (UUI)
You set the sip header name, encoding and protocol discriminator. e.g.

Genesys will do its thing and the extracted value will be available in Architect flow in the system variable Call.UUIData
Link to info https://help.mypurecloud.com/articles/about-user-to-user-information-uui/
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Simon Brown
Maintel Europe Limited
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