Thank you @DougBrowning and @Anonymous User for your ongoing assistance with this issue!
I've been doing some testing all morning based on your responses above and unfortunately the rollback error is still present. I thought I might have found the cause when Doug's first message pointed me toward the rating count calculations at the end of the survey and I noticed that two of those six fields had been improperly created as text fields in the feature service. I deleted the two original fields and re-created them as integer attributes (and had no troubles re-publishing the form with both Esri and form integer bindings now added to the EXLSForm), but unfortunately that correction didn't seem to have any effect on the rollback error.
Likewise I also converted all those 'element#Ratings' from 'calculates' to 'notes' - this doesn't seem to have any effect on the final structural rating calculation - and the rollback error still occurred after that update too.
Chris, I don't think the formulae you indicated in rows 101, 245, and 389 should be causing any problems. Those if/else calculations ingest decimals, but all of their potential outputs should be properly limited to integers (which matches that field's binding).
I'm including the log file from my iOS version of Survey123 (made sure to activate error tracking before completing and trying to submit an inspection), as well as the (slightly) updated version of XLSForm.
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Although... something I just happened to notice while re-examining the fields in my feature service... looks like the f#_critNuts_rating fields (lines 106, 250, and 394 in the form) were incorrectly created as text fields in the original feature class even though they function as integer fields in the form (as all the '####_rating' fields should). I'm going to fix those the same way I corrected the two erroneous 'element1rating' fields and see if that fixes it!