A couple of thoughts. It looks like those sights are going to be obnoxiously tall for a red dot cowitness to begin with, unless that's what you want. But, to me it looks like they're going to block a lot of the window. Also, the 407K / 507K sights have a rear sight built in, so you could possibly find a different front sight that would work correctly.
I think you need to do some measuring in regard to how tall the optic will be once mounted and the height of those suppressor sights.
For some comparison, here is an Sig Romeo 1 Pro with standard height sites.
It cowtinesses at the very bottom of the window.
You would need a plate to match up with suppressor height sights but [mention]Firehawk [/mention] could easily swap a front sight and go direct?
That being said, if he plans to run that with a can - it is pretty easy to use the top of the can to sight with for minute of man accuracy...