[muffin]

Maybe by convincing them that you really know your stuff when it comes to guinea pigs they might ask you stuff and trust you. I know someone who runs a rescue and when she's in P@H the staff will often direct questions to her because they don't know. On the other hand, unless they are prepared to listen they might not be willing to accept that you know what you're doing. Personally I would adopt a firm but non-aggressive approach. It's harder to go back in and be listened to if you've yelled at them. Been there!