@AMills96 - HubSpot wants you to verify your email sending domain (your root domain) and setup DKIM and SPF records as email providers now requries it. To achieve this, you’ll add a TXT record to SPF and a CNAME record to DKIM. This won’t disrupt your existing setup, except if you delete all TXT records for SPF.
That’s why HubSpot suggests combining your TXT records for SPF.
You can send email from your root domain. I don’t see any issue with CNAME setup. I’d suggest following HubSpot instructions, setup and verify your email sending domain.