Just to be clear ... the code placements in the original file were not determined by. I just clicked the "Send Mail" option in the WebAssist menu, and then let the extension do its thing.
I have, however, just tried the operation you suggested.
I.e. as in the file attached, I moved lines 307-314 below the email code the extension generated,
That was the only modification I made.
There was a successful interaction with Authorize.net which sent the usual receipt emails to me as (a) merchant, and (b) donor..
But unfortunately ...
(1) The confirm page goes completely blank after I hit submit.
(2) The confirm page code sends no receipt email.
(3) No receipt page appears on screen.
(4) And finally, Universal email does not send the personalized email.
I have reverted to the original page.
(I can also do this the long way round, and send out my personalized donor emails by hand as and when I get notified, by Authorize.net, that monies have arrived, if necessary)