Google Ads Purchase Attribution Issue

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Hey everyone,

I’m working on a unique customer journey and need some help understanding if Google Ads attribution will work properly in this case.

Here’s the flow:

  1. A user clicks on a Google Ads and lands on the website.
  2. They sign up using a HubSpot form. The user data and GCLID are captured in the CRM.
  3. The client manually reviews and approves the lead, which takes 2–3 days.
  4. Once approved, the client sends a payment link via email.
  5. The user clicks the payment link, returns to the website, and completes the purchase.

My concern:

Will Google Ads properly attribute the purchase as a conversion in this delayed and indirect journey?

If not, here’s what I’m considering:

  1. Should I implement Offline Conversion Tracking (OCT) for this kind of delayed purchase?
  2. Since HubSpot CRM captures the GCLID, can I pass that GCLID as a query parameter in the payment link to improve attribution?
  3. Is there a simpler solution, like storing the GCLID with Stape, that could help attribute the conversion correctly?

I’m a bit confused here and would really appreciate your thoughts or suggestions.

Thanks in advance!
– Monir