Originally Posted by WineCountryUA

UA policy is overnight / 12 hour connections requires picking up bags and rechecking. Might an agent do check-thru maybe / maybe not. No way to predict in advance.
Extensively discussed in Overnight, long layover/connection check through baggage question (consolidated)
But agree the allowance is likely going to be 2x50, especially if that is what the receipt states.

This may have been two separate awards and the TPAC segment was probably a business class rate as one segment was business class (and across two award regions).
Your long MEX connection is the basic problem and that is UA's policy. What is DL's policy and how long the connections were, will matter.