Small Engine Warranty claims are my part-time gig at our family owned small engine shop so I know how manufacturers work.
As far as Honda goes the dist. warranties thru them and sends a new motor to them (vendor) pending verification of the failed unit IF it is questionable. This usually isn't typical though. The relationship between the dist. & manu. is the real issue here. If this happened at our shop, we would have our chief mechanic check out the failure and determine the root cause. If the cause is easily defined as a part failure (spring,valve,etc) then we call our rep. and tell him what we found on the unit. He then would order another one from the manu. to be shipped to us for the customer. Then we file an online warranty, sending model, serial, number, original date of purchase & alot more info. to receive payment for diagnostic testing of the unit.
The only things that would raise suspicions are potentially warranty voiding violations such as aftermarket parts installed, low-oil shut offs disconnected, and things of that nature if the shop checking out the unit has a good working relationship with the manu.
The most important and ONLY thing the customer has to do is have a valid warranty! Once this is proved, Honda is obligated to replace the unit. A unit being called for by the manu. is between them & the dist. If unit is warrantied and the dist. has another unit in stock to give the customer, Honda will send them one to replace the in stock unit.
DO NOT GIVE THEM ANYTHING!!! These are not practices of true small engine professionals.