My Lexus IS300 now is ticking after the repair shop worked on the timing belt and valve cover gaskets.?

So, I will try to make this as short as possible. So I own a used 2001 IS300 with about 111k miles on it. After researching the lexus.com dealer records, I discovered that nothing was listed for the 90k service, no record of timing belt change either online or in the engine compartment. I did remove the VVTI cover and inspected it myself, no oil on it from leaky seals, the white Lexus logo was even still present on the belt, no shimmer or pully marks, no oil leakage that I could see really that was coming from the vvti gear.

I discovered that it had a pretty good oil leak, from what I believed was the valve cover gaskets both the left and right.

So, after much research and shopping around, I chose a small Toyota shop that also services Lexus vehicles. Lots of good reviews, A+ rating with 0 complaints from the BBB.

I tell them that I would like the timing belt changed, the valve cover gaskets changed out. They tell me it would take a day to complete the repairs.

I go to pick up the vehicle a day later, and they are still working on it.

I noticed them start the vehicle numerous times, like 3-4 times, and the next thing I know, the owner walks in and tells me he needs to get me a rental car (on him).

He said that the engine is now TICKING.

What the hell did they do?

I am planning on having all the repair work inspected at a Lexus dealership for peace of mind after they give it back to me with hopefully no TICKING, since it never did this until they touched it.