They should not differ much. The "J" means +/- 5%. The green "chicklets" a higher tolerance, but it won't be enormous. Both should be pretty close to .022 uf.
Unless the pots are different, my guess is that the difference is in the pickups. If you are not hearing much treble roll off, you probably need a "bigger" cap. Maybe .033 or .047.
A trick I learned from Weirdbits is to allegator clip in a parallel .022 cap to the one you have now. That will give a .044 value, which should sound similar to what a .047 cap sounds like.
On my last couple of builds I put the caps in last for just this reason. It's hard to know what cap value you want until you hear it
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