Not a comment about the scout and more a comment about Eagle Courts of Honor.  ECOH are a show.  The scripts are usually over-the-top.  Specific parts of the scripts are almost always "wrong" as no-one is being awarded a rank.  Maybe, "given" as here's the rank you were awarded two months ago.    The scripts usually have something like ... "Now, by virtue of the authority vested in me by the National Council of Scouting America, I hereby award the rank of Eagle Scout to you."  ... The person saying these words has no "authority" to "award".  Worse, the scout has already been awarded the rank and should be wearing the Eagle rank on their uniform.   Your choice is whether to attend the Eagle Court of Honor and / or participate in the ceremony.  

You have quite an issue on many fronts.  The first advice is grab a unit, ADC, or district commissioner for assistance.  If you don't know them, ask the district executive for the point of contact.  They should be able to help in many ways.  As for camping short-termed issue,  speak with the camp director about a provisional status that you can share a site with another troop and share adult coverage.  With the number of scouts you have, it should be doable.  Swapping leaders half week is common.  The late notice cancellation and physical is terrible news and you shouldn't have to personally pay for it.  If the CC is throwing up their hands, time for a new CC.  As for recruiting, word of mouth is the most successful recruiting tool.  Have scouts wear Friday class B shirt if they are willing.  All year round is cool, as our older scouts wear their philmont, OA, and jamboree shirts to show them off.   If all else fails, take a break for a month this summer from troop time.  Let some behind the scenes actions work among the adults and relook the situation.  May help to back off and relook after a short period.

And this is not too uncommon among really young eagles.  A couple of ideas pop in mind.  As for the COH, there may be minimal participation by those offended during the weekend.  Without publicly boycotting the event, a heads up to the parents is in order.  If someone feels he is not representing the Eagle rank, they can bow out.  I've seen this many times.  I wonder how the other troop Eagles reacted or will react to this behavior.  Definitely a leader/committee-to-parents meeting is needed.  Without hearing the Scout's side, not sure why he would not help out.  If he is the oldest member of the troop and highest ranking, I can see where he may get a big head with "I'm an eagle, I don't have to do it" mentality.  Worst case as stated above, may be time for him to perform or join a different scout unit such as crew or ship where older, more experienced scouts may change the behavior.

If his Board of Review has been completed and approved by National, he IS an Eagle Scout.  Whether he can remain a member of your Troop is another question.  Sorry this has happened.

@CuriousOne  welcome to scouter.com