SIP assistance - for audio conferencing Jitsi

We built a Rocketchat Jitsi self-hosted server so we could communicate privately within our team regardless of where we are. We have no trouble communicating for Teams-like sessions using computer/phone/tablet - as long as we use app or browser to connect. It is inviting people with landlines/cellphones to join the session - old-fashioned audio-conferencing - that is the issue. We would like to supply people who will be calling in from a phone with a phone number and code/conference ID that they can use to join the conference.

We have reviewed the following link -

and other similar guides but looking at the programming involved it seemed we would be better off finding somebody familiar with this type of programming to help us. @damencho suggested we post here.
Looking forward to whoever can assist us.

hi: yes if built correctly and managed it does work. How do you need help?
Technical “how-to” step by step? we do have a working version; however, it still has some small bugs but the important piece is there-intergration with telephony.
And yes it can take multiple call-in to the conference. As with open source no guarantees but seems pretty stable, and no we dont use twilio (never had never will) and we dont employ voximplant either.

Dear @arlesterc,
We sent you a DM. Kindly refer to that and reach us for more clarifications.
Thank you.

Best Regards,
Team Meetrix

Thanks for responding.

Please send our team an email at service@lineonecorp.com with subject:
Rocketcat Jitsi audio conferencing assistance
and someone on our team will contact you.