Here's some pictures to illustrate how to use my sequence:
Wall555 to 2x Tower333s.jpg [ 213.53 KiB | Viewed 424 times ]
You're sequence is working, it's just scrambling the 333 Tower Edges. Mine will mess them up too, but mine will isolate it to the LL.
You can use (R2 U)x2 (R2 U2)x2 (R2 U R2 U' R2) or (R2 U2)x3 to fix edges. They're not pure either, you have to account for things (like the E slice) to make progress.
If you want a more pure sequence you could use: (R2 U R2 U' R2) D (R2 U R2 U' R2) D' or some other variant.