Bottleneck - ACS assessment - Company name has changed

I have unique case, When I started my career in IT job they have me an offer which mentioned as Profession Service and later after a year they had converted and provide another offer with Trainee.
Should included my offer letter (E.g. ABC) when I submit my ACS?
I have a salary slip starting with the company name (E.g ABC) after an year onwards.
Now, this company has undergone different acquisitions and mergers .
Now, I have got the detailed experience letter from the start date till end date with proper software designation but the things it has different company name (XYZ) in the Company header , I’m struck now and not sure how to proceed.
Should i upload only the experience letter ? and fill up the name of the company as XYZ.
Not able to decide to proceed further. I need this experience to get my 8 years (coming from non-IT background)

Get a letter from Employer listing all names that it has operated with in the past and attach it with your work experience letter.

Thanks for the reply Anil. That’s not possible. Getting this detailed employer experience letter was a big daunting task to get from them. I don’t think they will put my old companies list in it.