Did you experience either of these Colosseum tours?

Tickets and tours can be found at
https://colosseumtoursinrome.com/

Haven't done either but I wouldn't personally book any tour of the underground through a 3rd party (Viator, Get Your Guide, etc.) or independent tour company. If it's important to you to access it, book it only through Parco Archeologico Del Colosseo's own official ticketing website (below.) It is not Coopculture, as stated in the website linked in the previous post, and hasn't been since this past spring.

https://ticketing.colosseo.it/en/

Too many visitors have been disappointed by having their tours cancelled right before their trips due to those companies not being able to get tickets they've pre-sold to their customers. Underground tickets are hard to land!!!!

I have taken both tours…the Underground and the Attic.
If you are trying to buy tickets for one of these on the official site, keep in mind that the tickets are hard-to-get and usually sell out within minutes (often seconds) after they become available.

When next month are you going?

Our entire family of 12 is going toward end of November and I will be attempting to purchase Attic tickets for my son and daughter-in-law and for my son-in-law and his father the end of this month.

Attic tickets currently are being released 30 days in advance and in 20 minute increments tied to the admission time. Underground tickets are also being released 30 days in advance…also tied to the admission time.

https://ticketing.colosseo.it/en/eventi/full-experience-attico/

https://ticketing.colosseo.it/en/eventi/full-experience-sotterranei-e-arena/

You need to be online at exactly the time the tickets become available…Rome time (and remember Italy goes off DST on October 27th at 3am, whereas where I live in the US we do not go off DST until November 3).

Personally, I greatly preferred the Attic over the Underground.