Did Lockheed test the TriStar in conditions similar to a century of operation?
If a plane of the L-1011's range makes two flights per day for a century without any maintenance breaks, that would be 73,000 flights.
The answer is yes, more or less, literally, if you look at wing loads, or pressurization, respectively. If you account for AOG (aircraft on ground) time, then most certainly yes for both:

A total of 1,696,000 load cycles, simulating 84,000 flights, were applied to the fatigue test airframe. The first 52,000 flights included all loadings, including pressurization. The last 31,500 flights omitted fuselage pressurization, while wing loads were increased from 10 percent to 20 percent over the basic spectrum. This amounted to an equivalent of 115,000 flights. A specific number of load cycles applied by hydraulic jacks to the fatigue test airframe equates to the loads seen in one flight of the aircraft. [emphasis mine]

Since MSN 1000 (second airframe) reached the equivalent of 115,000 flights, it means it did not fail before that, but that doesn't mean that lessons weren't learned and applied to the production airframe, which is one of the purposes of such tests.

Upton, Jim. Lockheed L-1011 Tristar. Specialty Press Publishers and Wholesalers, 2001.