cvxCrv is staked into a BaseRewardPool, while cvx is staked into a cvxRewardPool. There are not many differences between the two types of contracts except for the cvx contract deposits rewarded CRV into the CrvDepositor and is exchanged to cvxCRV before being claimed.
The address of these contracts can be founds on the booster contract:
var cvxStakingContract = await booster.stakerRewards()
var cvxCrvStakingContract = await booster.lockRewards()
VeCRV fees (3CRV)
vecrv fees (3crv) are distributed to a child reward contract of the cvxCrv staking contract. You can find it in the extraRewards array there, or simply from the booster contract at booster.lockFees()