Hi Diskev
Welcome to the community forums
We ask members not to make multiple threads on the same issue, this is so we can assist within one space more efficiently and clearly and not ask any repeated questions. This also helps other members that might have similar issues or questions find all the information in one thread should they need.
In response to your question, we wouldn't be able to install an external omni box internally in the home. The omni box would need to remain externally on the outside of the property. If the omnibox needs to be moved for your home extension, you'd need to speak with the team to discuss what can be done in terms of rewiring and relocating. There may also be additional charges for this request depending on the work that is needed.
Let us know if this is something you're ready to arrange at this point in time and we can email the team for you when needed.