SCEP or ADCS Connector communication to Jamf without inbounds

Hello,
I'm actually stuck with a company who has a Jamf Cloud platform and they need to distribute certificates from within their environment. The only point is that they don't want any inbound connections even in DMZ.
I checked the options for SCEP and the ADCS Connector for DCOM protocol and all of them need an inbound on port 443.
Any ideas how to do this ?
Seems like Workspace ONE is able to do this with a connector contacting the server frequently to see if any certificates needs to be distributed but I didn't find anything similar with Jamf...
Thank you !