Since it's a virtual window I don't think what you think is the title is that for the system. I'm guessing MEP is seeing the correct window title which is hidden. The window title you're seeing is the one runnon on the virtual server. If that's the case, then you will not be able to access that string of characters. Activation using that code will not work.
acantor: calee showed what that string is in a prior post. It had "Remote" at the end of it and the string is not visible.
(what is it with lower case these days... 🙂 )
I think your best bet is to find something that has that code available and can be collected. I would use a control like the one you mentioned where a barcode was also visible. Trigger the macro on the appearance of that control, collect the text from that control, evaluate it for the desired sting, and if apparent issue the warning or whatever you want to do. Note that all but your annunciation at the end will be instantaneous and invisible to the user.
My concern is that a virtualized app is probably just graphic depicting the app running elsewhere. There might just be one big control showing a graphic. Like a video player. When you click on a button, you're actually just creating an even to send a click to the remote app at that coordinate. All your inputs are being executed by proxy. If so, MEP will not be able to access the real control on the server. However sometimes there will be a pass through for printing, file savings, and clipboard, just like in a VM or remote control app. If so you could use the VM apps invisible title as activation, then do something with the keyboard or mouse like Ctrl+A, or click on a coordinate to highlight the text in the remote control, fire a Ctrl+C at it, and then have it copy and transmit the text to your local clipboard for evaluation. There might be some delays so I would start experimenting with at least 100 ms delays between steps then reduce them as far as reliable.
If I were you I'd first see what the MEP Windows Controls commands identify with the picker tool and then see what text I could get from there. Also it will show you want to local (accessible) window title is. In this graphic you can see the title of the window for which control I was selecting was "Macro Express Pro - Script Editor [Test]:". Show us what you find if you need more help.