Can that property really be Sold?

I have a question for an Ohio REALTOR:

Can a property be listed by a guardian who "has the authority" to sell a property only to find out after the buyer has made an offer, it's been accepted, the inspection has been made, the appraisal has been done and now the property was suppose to close this week, but wait- the property can't be sold? 

The guardian who "had the authority" now can't represent the property??  What's going on here?  And should the buyer be out any expenses for inspections and appraisal?  Of course, I hope the enerst money would be returned in full. But again, what's going on in this situation?  There are several players involved in this, the seller, the guardian, agents, the bank and the buyer.  ARe there just too many playes to keep this all straight?  And after the closing that didn't happen, who is responsible for reimbursing the buyers their expenses that incurred in this transaction that was aborted?

Any advise for my friend?  Please comment!