Hey there! Unfortunately, Norbert's Gambit is kind of brokerage dependent. For example, Questrade has CAD and USD in each account, so there is no need to move shares to different accounts. RBC Direct Investing journals shares right away, so there's no need to wait 3-4 days etc.
The easiest way though for sure, is to purchase DLR.TO, and then get a hold of TD Direct Investing to journal those shares over to DLR.U.TO. You wait 3-4 days for this to process, then sell those shares, and you will have USD.
But to me, it seems like you have USD specific RRSP. So, you may need to buy DLR.TO in a CAD RRSP, and then transfer over?
Ultimately, the process is very simple, DLR.TO > Journal to DLR.U.TO > Sell.
Now, because I've never used TD Direct Investing, I have no clue if this video is still relevant. But, check this out
https://www.youtube.com/watch?v=BwUyQm60F_k