As always, I’ll begin by stressing that I do not know what you are supposed to do, as that decision is to be made with your personal rav and mashpia who will consider all facets of the question. I will share with you some letters that the Rebbe wrote about summer camp in general and to someone is a similar predicament as yourself:

(1) “It is understood that the idea to make a summer camp is a good one and it should be even larger than the previous years. I have written many times to people which are active in these type of things (making camps) that camp has a big effect on the (involvement of the students) in the winter that follows the summer in addition to the obvious benefit of the opportunity to influence those attending the summer camp as they are not distracted with other learning obligations.” (Igros, Vol. 11 p. 145; #3533).

(2) On Lag BaOmer 5746, the Rebbe said the following: “It is now an opportune time to influence parents to send their children to proper (frum) summer camps, permeated with the love and fear of Hashem. As we spoke many times, we see that the effect of the summer camp on children — especially an overnight camp — is in many ways stronger than the effect of schooling.” (Likutei Sichos Vol. 37 p. 124).

[An interesting finding from the 2017 PEW study: According to the Pew findings, 44% of practicing Jews reported attending Jewish overnight camp as opposed to only 18% of those who are non-practicing.]

(3) “Just as in your physical health, we find that the health gained in the summer (through activities etc) benefits the body the entire year, so too in a spiritual sense: The spiritual health of the soul received through the proper education in camp should continue the entire year.” (Igros Vol. 22 p. 316; #8512)

And now to your specific question:

(4) “You write that you are working hard so that you should not need to remain in your job in the summer camp: This is not the behavior that is understood (and expected) by our Rabbeim. This is true even if you did not have to try hard not to be in the camp (that you should still try to go).  It is obvious that if someone was given the privilege to be involved in education, this should be his “Mitzvah that he is extra careful in” and certainly not to be actively looking for opportunities not to be involved!?

Even if, as you claim, the camp could find a replacement (it is still not a good idea): The work in the camp, in comparison to the previous year, is growing and it is hard to know in advance how the new person — or someone with this new position — would adjust to this position. It is not worth even entertaining this doubtful situation for something that is a once a year opportunity which has such a big effect on the rest of the year.” (Igros Vol. 20 p. 17; #7464).