Email Outreach Options for Microsoft Resellers and IT Partners

Hey all, quick question on the Clay email sequencer. I principally work with Microsoft Resellers and IT partners. I run our campaigns through LinkedIn as I feel its the best medium for a longer tail sales cycle and for building trust. Lately I do have a few clients that would like to add Email outreach and I was wondering if the client/partner provides the email inboxes, will I still be able to authorize them on Clay? Assuming they have added Clay as an approved app in their setup? For n8n i had issues adding other accounts as i needed admin permissions and not sure if it would be the same here. Is there a way to accomplish this without too much inconvenience for the client? My other option is buying the domains and inboxes myself but that drives up costs for them. They also have a lot of inboxes they can spin up and prefer doing it in house. Thanks in advance for any help. and if this isnt the right channel. please let me know.