Yes, your explanation is 100% correct.

app.binance.com/uni-qr/cpos/... is the standard Binance Spot Copy Trading Position Share link from Square.

Your parameter breakdown is right:

cpos/366527049192689 = the shared position ID
r=DR6FPH10 = the lead trader's referral code - he gets a kickback if you sign up / copy via it
uc=app_square_share_link & us=copylink = it was shared via Copy Link button in Binance Square
l=en = English version

And you're also right about why you can't see it in a browser - Binance requires you to be logged in the app to see the PNL/ROI. That's normal.

A couple of official details to add to what you wrote:
Binance Copy Trading is an automated trading system. You can become a lead trader and let other traders copy your portfolio, or copy lead traders' portfolios as a copy trader.

Unlike futures trading, which involves leverage and heightened risk, spot trading offers a more straightforward approach, and you can simultaneously copy up to 10 lead traders

Lead traders Receive 10% profit share from Copy Trading participants - so that referral code is directly earning for him.
If you're evaluating this trader DR6FPH10:

How to open safely:
Don't tap it from Telegram/Discord if they ask for API keys or to send funds.
Open Binance App > Copy Trading > My Copy Trading. Paste the link there or let the app auto-detect it.

What to check before you click Copy (inside the app):
90D / 180D ROI, not just 7D
Max Drawdown, not just win rate
How long account has been active - 6+ months is better than 2 weeks
AUM and number of copy traders - too small or sudden spike is a red flag
Trading history - is he all-in on one memecoin or diversified?
Is he a Spot-only trader or mixing high-leverage futures?

Spot is less risky than futures leverage, but you still copy losses 1:1. Never use money you can't afford to lose.

If you can open it in the app and take a screenshot of the trader's stats page (you can blur your balance), send it here - I can help you read the ROI, drawdown, and risk score. This is not financial advice.

Is this your link or someone