will the poe be enough to power 4 ip cams?
Are you asking if one PoE output port from the CRS328 can drive 4 cams via the PowerBox? If so, that seems dicey. By my math, you only have about 4 W of power per port under this configuration. That's 48 V nominal from the CRS328 @ 450 mA = 21.6 W. Subtract the 6 W the PowerBox itself needs, leaving 15.6 ÷ 4 = 3.9 W per port.
The hungriest cam I have here is a modern 4K camera configured for high video compression, and it's drawing ~120 mA, so at 48 V nominal, that's nearly 6 W of draw. A less hungry 1080p cam is drawing about 5 W.
I expect that there are IP cams that will run from the 3.9 W available, but you'll have to sacrifice something to get it: lower resolution, lower frame rate, poorer compression, or some combination of the three.
It'd be much better to home-run those cams back to the CRS328, which has plenty of grunt for this task. The 21.6 W number from above is then per-port rather than fanned-out through the PowerBox, and you don't have the PowerBox's overhead, either.
There are limits above this, but you're highly unlikely to run into them, and if you do, you can take advantage of the fact that these switches group PoE according to
the underlying switch chip groupings, so even if you do manage to overload one group, you can rebalance things by spreading the PoE load to the other groups.