This has absolutely nothing to do with Scout Spirit. Here's a direct quote from the BSA's own advancement guide:
We can say, however, that we do not measure Scout
spirit by counting meetings and outings attended. It is
indicated, instead, by the way he lives his life.
If, in fact, it's actually a problem with meeting the "since joining" activity requirement, The BOR may be correct - but it has nothing to do with Scout Spirit.
If it has to do with a Troop's participation requirement, that requirement must be spelled out - in advance - to everyone. It has nothing to do with Scout Spirit.
I am curious about something - the Troop Committee's vote. Are you sure the Troop Committee took a vote to deny a BOR, or was it a BOR that denied advancement until one more camping trip was completed? It's a rather big difference - If your son did, in fact, sit for a BOR and they denied him advancement for this issue, the BOR may have acted correctly and just got terminology wrong. If the Troop Committee gets together and votes on when Scouts can have a BOR - then they are not only doing it wrong, they are wandering through a canyon maze, they are so far off true north. Committees don't have a say on whether a Scout can have a BOR - the SM tells the Committee that they need to convene a BOR for Scouts A, B & C and the Committee convenes the BOR. They don't vote on whether to have them or not.
If the Troop Committee took a vote about whether to convene a BOR, and the Scoutmaster sat back and didn't raise a stink, then my suggestion for you would be to run - run and find a new Troop - because you can't fix stupid like that.
