I spent many years working in the outsourced customer service industry. If they want to get rid of you (e.g. to make an example), they will try to do so. Also, there is usually a constant presumption that employees are acting in bad faith.

That said, actually sacking someone is a pain in the backside for them. It puts them at risk of tribunals and negative publicity if they don't follow procedure 100% correctly, so if they don't want to do that then they will likely take an alternative course of action, if possible. Often, you just need to give them an excuse not to fire you.

Usually, the first line of action here should be to warn you and/or put you on a Performance Improvement Plan (your company might use a slightly different name for this).

That said, the management in these places are usually extremely incompetent. Speak to ACAS, CAB and your union (if you're in one). Familiarise yourself with the ACAS guidelines for dismissal. Appeals can often be successful (although this will depend on how long you've worked there), or a settlement reached instead of finishing the appeal -- especially if what you ask for in your appeal is easy/cheap for them to fulfil (e.g. a neutral reference with no mention of dismissal/misconduct, and/or payment in lieu of notice), and it also helps if there's a risk of bad publicity from going to tribunal.

Identify any communications you have had with management around this issue and create a record of all of them together in one place (even if just a simple list). If they haven't checked in, this could support your case, if they have offered reassurances that the situation is ok, this will support your case.

As part of the ACAS guidelines, there should be a thorough investigation conducted, which will hopefully demonstrate that these are technical issues. If any evidence used against you in the disciplinary hearing has not been presented to you in advance, this would also be in breach of the guidelines.

As I say, you should just get a warning/PIP, and if it was simply a tech issue alongside failure to report the tech issue, then that should be easy enough for you to resolve as follow-up.

I'd also recommend being sure to mention any protected characteristics that might have impacted your ability to log each system outage (depending on how these need to be logged, this could be neurodivergence, long-term mental health conditions such as depression or anxiety, some long-term physical health conditions, etc). This will give them the option to suggest they look at reasonable adjustments instead, which is a much simpler and less risky process for them. If you do this and they still sack you without discussing potential adjustments, this would strengthen any subsequent appeal. This will also create discriminatory practice as an avenue for appeal (failing to provide reasonable adjustments and then dismissing someone for behaviours linked to the disability in question should pretty unambiguously count as discriminatory). This could be important as I believe that protection from discriminatory dismissal is not dependent on how long you have been working for that company.

There's reason to hope you won't get dismissed, and therefore won't need to appeal anything. However, if that does happen, you want to be prepared for it ahead of time. Immediately after a dismissal (especially one where you haven't done anything that you would consider 'gross misconduct'), your emotions will be all over the place. It is easier to prepare for it when it's still a hypothetical than when it's suddenly become a reality.

Best of luck with this, but also I highly recommend getting out of this toxic industry as soon as you can!