Keep it simple. [ I say that cause I'm a simple Bloke

]
If you feel that you may get too much pressure just before the throttle
plate. Could you provide another pipe to route Hydroxy to just after air cleaner and before the turbo. [ this may be all thats needed in total ]
But you could have a one way valve on your throttle plate tube then hydroxy would flow to the " before turbo pipe ".
While you are at it...... are you going to run water injection to cool
the intake charge???????
Its like running an extra Intercooler - Internally.
I believe you will find a great improvement but adding Hydroxy - as long as
you get a decent amount and make it efficiently.
-
If you worry about making too much Hydroxy - run the over Pressure switch in your Unit - to cut power to the system when this happens.
The unit will switch on/off to keep the Hydroxy pressure at reasonable level and you wont waste Energy.
Glenn