If the frog is in quarantine, I would definitely ditch the moss for now and just use dampened paper towels that you change every day. This way, you don't have the risk of the frog seeing a cricket that has been hiding for a while, jumping down to eat it, and accidentally eating some moss and becoming impacted. Once you have him bowl fed and/or once his quarantine time is over (3 weeks to a month is recommended) you can place the moss back in.