I can’t speak specifically to why a 32-spoke replacement was chosen for your repair; however, it may be due in part to the supply chain shortages the cycling industry has been experiencing throughout the last year. I’m sorry that this wasn’t pointed out to you while you were in for service!
I would recommend contacting the shop that completed your repair to discuss the wheel choice with one of their Technicians or Service Advisors. If the wheel that was installed does not meet your needs, you can always return it under our 100% Satisfaction Guarantee.
As for your spokes, I would say it is unlikely that the spokes on your original 36-spoke wheel (or the included replacements on the frame) are the exact same length as those on your new 32-spoke wheel. They may be close enough to get by, but without measuring the spokes it isn’t possible to be certain if they’re compatible.
The technicians at your local REI Co-op Shop should easily be able to measure what length replacement you would need for the new wheel and get you some spares which would fit into the spoke carry feature on your chainstay.
Enjoy your upcoming tour!