LT G-Rated Tires

The technician stated to keep the tire pressure at the Vilano's manufacture's posted label pressure of 80 PSI., not the tires pressure indication of 110 PSI.

Very bad advice. Were talking tires used in a trailer with close spaced axles which have different pressure needs than the tow vehicle with tires at the corners.
The trailers tires side scrubb (twisting) as its pulled around corner or backing up maneuvers. Max pressures help hold the tires normal shape and fight interply shear and makes a cooler running tire.

Tire experts.....tire safety blogs....even tire mfg recommend max sidewall pressures for tires used in a trailer position unlike tires on our trucks.

Now if the trailer has been severally over tired then at some point max pressures would be too much.

If thats the case then I like this from;
rvsafety.com

Tire Load and Inflation Ratings

Note: Towable – Travel Trailer/ 5th Wheel owners Due to the severe use conditions experienced by tires when axles are very close together – tire industry experts recommend maximum (sidewall) inflation pressure for towable tires unless this causes a sever over-inflation situation (20psi+), often referred to as the ‘basketball effect’. If this is your situation allow a 10 – 15psi safety margin above the minimum required inflation pressure.

And rvtiresafety.com (Tireman9 on several rv websites);

**When not driving in a straight line there are special side loads on multi-axle trailers because the tires are fighting each other because they are not "pointed" to the center of the radius of the turn. These loads cause interior structural tearing. Sometimes 24% higher loads than those seen in tires on non-trailer application. Initially tearing is at the microscopic level but with time and repeated cycles these forces grow which can lead to small cracks at the belt edges as seen here at the arrows.
and
You can lower these forces by either decreasing the load 24% on the tire (probably not something you want to do or may not be able to do) or you can increase the inflation to stiffen the structure and decrease the slip-angle. In this case you could increase the tire inflation from the minimum inflation needed for the static load to the inflation associated with the max tire load as molded on the tire sidewall**.