The chief idea is to create interesting moments using the correct trigger tokens that the sales could refer to instead of looking at the sales alert email for all the key prospect engagements. If you still want to go with the latter, you can always create fields to store the last source/interaction detail, have a setup to update those, and include the fields' data in the email.
In most cases, the last interaction would have caused behavioral score change, triggering the sales alert email upon reaching certain thresholds. Of course, this is difficult to manage and would need you to have a solid alignment between your scoring model and interactions (which is usually difficult to manage given that there could be so many sources/channels that would not trigger the score changes, the reason people use interesting moments as it makes the job of a marketer easy).
Any reason why you don't want to use interesting moments and instead want to add the last source details in the alert email? With interesting moments, sales are able to see all the data and not just the first/ and last interaction of a person - they could get (or atlease make a close estimate) of the interaction that would have made them reach the threshold by looking at the interesting moments.
.png)