Apologies for bumping an old question. You've surely figured it out long ago, but the question remained unanswered and is still relevant for others, so here goes:
The missing transaction is due to Plutus Playground's requirement that the simulation include a final 'wait' Action of at least one slot for the last transaction to be processed. Would make sense for Playground to automatically process 1 additional slot after the last declared wallet action, but for now it doesn't.
I've also noticed that the Trace records are truncated, but it also occurs when the simulation being evaluated runs as expected. Not sure whether it's ubiquitous or peculiar to running Playground within WSL2.
On the topic of interpreting the Logs and Trace listings, here are three points that may make them easier to track:
a. Logs area is presented sequentially for the entire simulation, slot-by-slot.
b. Trace is presented sequentially per Wallet (in case you're as confused as I was at first about the slot numbers not being sequential). Unfortunately, I haven't figured out what the "Iteration" numbers represent yet.
c. It's easy to become lost or overwhelmed with the amount of data in Logs & Traces, but by including a unique tag within all of your traceIfFalse and logInfo messages (e.g., appending
[dbg] to each message), and then searching for that tag on Playground's results page, you may find it much easier to track the event flow.