If you want piece of mind use a pure diazo emulsion for that 2k job. I've done 6.5k pieces with 2 screens, coulda been done with one but it was printed over 2-3 days and wasn't cleaned out nicely enough once. SP-1400. Just ask for a sample from Murakami. We buy 4 quarts at a time for the gallon price and use it for water based printing.
I doubt this happened to you but if that emulsion was mixed over 4 weeks ago that could be the problem. When we got dual cure emulsion in 5 gallon quantities we ran into that problem once and changed back to 1gal for dual cure.