As I stated, I'll complete my documentation here. TL;DR: Miles posted to Aeroplan 14 days after initiation on Capital One's website and calling (other than to clear suspected fraud alerts) seems like a waste of time; so, likely best to just wait it out.

1) 9/13/23 10:17pm Eastern: I initiated a transfer of 340,000 Miles from my Venture X Business reward account to Aeroplan. [no email confirmation received]

2) 9/14/23 2:46pm Eastern: I received and answered a call from Capital One Fraud Dept. (800-239-7054) inquiring about potential fraud connected with a recent transfer of miles. Before he could say more (after he confirmed my identity), I confirmed the exact amount of the transfer and the mileage partner. He seemed pretty satisfied that I could do that at the phone number on the account and indicated that he would close the fraud case and the transfer would be processed.

3) 9/14/23 10:56pm Eastern: I called Capital One to inquire about the status of the transfer (as none of the miles appear in my Aeroplan account). 59-minutes of speaking with various Capital One reps leaves me just to wait. It took 37 minutes before any rep (bounced around between Rewards Dept. to Fraud back to Rewards back to Fraud) acknowledged that it wasn't actually processed at the time of (1) above and there was a Fraud case (see (2)) that had been resolved at 2:47pm Eastern.

4) 9/18/23 6:02pm Eastern: I called Air Canada Aeroplan and was told that it can take up to 14 days. Pushed further and connected to support (55-min additional wait) to be told there was noting they could do but wait and maybe it was held-up on Capital One's side.

5) 9/19/23 2:28pm Eastern: I called Capital one and spoke with multiple departments (including Fraud and Rewards) and one agent even (claimed) to call Aeroplan while I was on hold. Was told that on Capital One's side they show as transferred (dubious because Capital One ended up sending an email on Day 14) and that it can take up to 14 calendar days until the miles appear in my account.

6) 9/20/23 award space for my intended booking disappears.

7) 9/26/23 award space for an alternate booking appears (and Aeroplan is the better deal than other *A). Amex transfers have resumed. I transfer INSTANTLY 400,000 Amex Membership Rewards to Aeroplan and book the alternate flights.

8) 9/27/23 8:45am Eastern: I log-in and see no miles have been deposited in my Aeroplan account.

9) 9/27/23 8:53am Eastern: Capital sends an email that 340,000 miles have been moved and my "miles transfer to Aeroplan is all done!". I log-in to Aeroplan to find 340,000 miles that were not there 8 minutes prior!

I think some take-aways are:
A) Clear fraud alerts related to transfers
B) The transfers are not completed until you receive the email (so, my 100+ Air Canada log-ins to see if miles had appeared and my hours of phone calls during the course of the 2-weeks were likely a waste).