Searching Messages app inconsistencies, one time text message is there, other time it's not (nothing is deleted)?

So while preparing a case that involves screenshots from the Message app on an iPhone XR, I noticed that one message bubble [the bubble near the bottom of the screen, containing "U dont respect that so. Thats fine ... bye ... ...," where the "…" are emojis] appeared on a screenshot, but when I went back to that same spot, time and date, etc., that bubble was gone (Screenshot 1 below). But when I searched a phrase from that bubble, it was there again (Screenshot 2 below), where it should have been all along.

What's goin on? Why are some bubbles not showing where they should be in the text thread, but then show up when you search them directly or simply on another occasion?

These shaky inconsistencies make it hard to trust the Message app in cases where a person is depending on accuracy and evidence. Really disconcerting.

Anyone know what's going on? Why this app works this way? And if there are workarounds to guarantee accuracy, and that all existing bubbles appear as they should?

1. "U dont respect that so. Thats fine ... bye ... ..." missing?

2. "U dont respect that so. Thats fine ... bye ... ..." shows now?