[details=“English Translation”]Every time I ask him to help with the dishes, he pretends not to notice.
[/details]
Wiktionary makes me believe this is an idiom from Venezuela. I’ve only heard “hacerse el sueco” (in Spain).
musiú m or f by sense (plural musiús or musiúes)
(Venezuela) a foreigner, especially a blond-haired one
Es hacerse el sueco, no ‘en’ sueco. También se usa’ hacerse el loco’ , ‘ hacerse el sordo’, ‘hacerse el tonto’ … etc. Hacerse el musiú no lo he oido en mi vida.
That was a typo (autocorrect). Being Swedish, I have heard that expression quite a few times. That said, sueco appears to an alternative spelling of zueco (clog, wooden shoe).
Several theories exist, the most likely being that the expression comes from the Latin word ‘soccus’, which eventually evolved into zuecos.
Another possibility is that it comes from the fact that Swedish sailors, when they arrived in Spanish ports, pretended not to understand Spanish so that Spanish merchants could not complain to them about goods, prices, etc.
I am sorry to tell you that due to your level of Spanish (very high) you will not be able to ‘hacerte el sueco’ in Spain. 
