Have the sales team fly in and kick them out, etc. Try to get the highest level people possible engaged, then get unreasonable. All of these folks will report some crazy deal opportunity and their chief sales guy will be at their throats back at home. You’ll get the concession you need. Best advice is to just avoid suppliers like this.
someone used the word on my once i think. 'concession'. they made a 'concession' for me. don't think i twisted their arm or anything.
don't like these games these big players play.
[0] https://www.priceintelligently.com/blog/j-c-penny-s-pricing-...
That's why companies don't publish their pricing, to prevent something like this.