Yes, it would be possible. It would happen in case where your friends buy an item in store and then they claim a refund of the purchase, but it will not be lost if your friends account is deleted.
In the same time, Loyalty points will be deducted only when the account of your friend will be deleted.
Cipsoft official reply regarding Loyalty Points:
"If an invited account gets deleted, the loyalty points that the "recruiter" earned through Tell-A-Friend will not count anymore towards the recruiter's loyalty score (which means the points that were added through Tell-A-Friend will be subtracted again)."
https://www.tibia.com/forum/?action=thread&postid=37116782#post37116782
Cipsoft official reply regarding Recruiter Outfit:
"> if i receive my Recruiter outfit ...
> and later my friend be deleted ...
> i will loose my outfit ? ? ?
No, the recruiter outfit is a reward that is bound to a payment made by your invited friend via the Webshop. So you'll only lose the outfit/addons if your invited friend revokes the payment (and you fall below the required number of invited friends who bought a product). "
https://www.tibia.com/forum/?action=thread&postid=37121561#post37121561
Items which can be refunded:
- Mounts and outfits purchased within 14 days, afterwords are non-refundable
- Hirelings, Hirelings Dresses and Hirelings Jobs- purchased within 14 days, afterwords are non-refundable
- (Express) Charater World transfer - no time limit.
Source: https://www.tibia.com/support/?subtopic=gethelp&topicid=5
Connected to the question - https://www.tibiaqa.com/5180/can-i-return-items-bought-at-store