Why are my Index Exchange header bidding issues acting like a toddler?

Hey everyone, hoping for some collective wisdom here before I start talking to my screen like it's a recalcitrant child. We recently pushed some updates to our ad server configuration, specifically around our header bidding setup, and now Index Exchange seems to be throwing a tantrum.

The main issue is a noticeable drop in fill rates and significant discrepancies when comparing Index Exchange's reported impressions with our ad server's numbers. It's almost like Index Exchange just decided it doesn't want to play nicely anymore, especially with certain geo-targets. We're seeing lower eCPM for Index Exchange compared to other SSPs which usually perform really well, making me suspect some core header bidding issues.

So far, we've checked our Prebid.js adapter configuration for Index Exchange – everything looks by the book. We've also monitored network requests in the browser console for bid responses and timeouts, and nothing immediately obvious is screaming "ERROR". We've cross-referenced our ad server line items and targeting to ensure no accidental exclusions, and reached out to our Index Exchange rep, but the initial suggestions haven't really moved the needle. Lastly, we've verified our analytics integration for any discrepancies in data collection.

Has anyone else experienced similar Index Exchange header bidding issues after recent updates or tweaks? Are there any hidden settings or common troubleshooting blind spots specific to Index Exchange that we might be missing? Or perhaps a third-party tool that's particularly good at diagnosing these kinds of programmatic headaches? Any advice on how to get Index Exchange to stop acting like a toddler refusing to eat its veggies would be hugely appreciated.