Thank you for your patience. It sounds like this boy is definitely only passing very small feces and quite a bit of liquid. There are a few possible causes for this including anything from colitis due to stress (not having his owner around), to an infectious issue, or of course a potential foreign body due to the drumstick he ingested a while back. If this was a foreign body issue, then I would have expected him to have some vomiting, or to at least be off his food right now, and that doesn't sound like it is the case thankfully.
Hopefully his owner has him up to date with his deworming treatments, but it would definitely be worth checking in with them to ensure that is the case, and if it isn't, then you will be able to get an appropriate allwormer from your local veterinary surgery. For now, I would recommend changing this boy over to a bland diet of cooked, boneless, skinless chicken breast and boiled white rice for 2 - 3 days. This bland diet may be enough to settle down any mild gastroenteritis he may have developed here. Also make sure he has plenty of fresh water available and do encourage him to drink. Make sure you and your family aren't giving him any other human treats, as this could also be a potential cause for his issues.
As far as the bone goes, good work giving him the roll. Hopefully that was enough to cover any sharp shards of bone that could have caused an issue on their way through. If he starts vomiting, passing blood or goes off food, then you will need to get him down to his regular vet for a full check up and possibly xrays to rule out a gastrointestinal obstruction or potential perforation. Again this is less likely as you haven't seen any of the symptoms that would indicate this, but definitely keep this in mind.
Best of luck with this boy and hopefully he is producing nice firm stools very soon. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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