My neighbours were having a regular party in their home once and let nearby residents know in advance, it's common curtesy and then he could have planned ahead and booked a cheap hotel room to sleep in that day

you'd book a cheap hotel to avoid noise...? you could just invest in a hearing reduction device.. working nights and stuff doesn't mean your neighbour's should be in trouble for noise during the day, and you can't be surprised, working nights and all.. I've never heard of a neighbor knocking on doors to let people know of a party at midday. . at night, late etc, yeah... but at normal hours there are no noise restrictions where I live.

Let's hope this wedding doesn't go well, the last thing OP needs is for his neighbors to decide they can make some spare cash renting out their yard for services and receptions.

I don't think that's the problem or the solution, #10.

.. Or let's hope it does go well, partly because they didn't do anything to deserve it to go badly, but also because by your logic, if it goes well they won't need to hold anymore mariachi band-weddings while OP is trying to sleep..

mariachi bands are awesome.

I honestly get too scared to use earplugs/earbuds at night because I'm afraid I won't hear my alarm to wake me up for work.

There is a special alarm clock for deaf people - vibrating armband. People put it on their wrist [arm, ankle, somewhere], set the time and it vibrates at that time.