Elaukai Neshama or Elaukoy?

I recently had an email discussion with R' Rallis Wiesenthal about his tefiloh Sefas Yisroel. I had noticed that while R' Hamburger's madrich says to spell אלקי with a kamatz, the Sefas Yisroel follows the nusach of using a patach. He mentioned to me that this was due to his research, which showed that Elaukoy was presented in the Avaudas Yisroel (Baer) as following Yitzchok of Satanov, a maskil, whereas most other siddurim, including pre-Rödelheim ones printed in Homburg and Frankfurt a/M give the nusach of Elaukai.

Has R' Hamburger discussed the mekor of this nusach and why he recommends it for B'nei Ashkenaz?

The instructions in R' Poupko's translation say to say Elaukoy, while the Hebrew edition does not discuss vowelisation.

Sources:
Madrich (en) p. 46
Madrich (he) p. 22