“... i took everything off and check to make sure the timing marks lined up correctly. they did....”

If you are using the timing marks on the crank damper pulley to verify timing be aware that on a lot of the 700/900 cars that timing mark may be unreliable. That’s because the outer pulley ring has a way of spinning independently of the inner hub part due to deterioration of the rubber isolation between the two parts. If the engine would at least run you can paint a reference line across the inner hub, rubber section, and outer ring and see if there is any slippage after running for a while. In your case you could pull out the #1 spark plug and compare piston TDC vs the timing indicated TDC.

Resistance values. Distributor should be near zero on all posts. 7 is probably close enough. You didn't mention if you checked all five posts.

Rotor. Should have a resistance value stamped on top of the rotor. I don't have any around here - ran out of red block volvos about four years ago - but I recall seeing a 2K stamp on one. Different years may have different values.

You seem to have eliminated the usual suspects. I would probably go back and check spark at the plug wires again, using the old plug/ laying on the manifold method, making sure that all the distributor wires are fully seated. If still no spark, and the timing belt is properly aligned and turning, the next suspect is the distributor. Maybe something sheared where the shaft mounts into the cam? Can you turn the shaft by hand?

Some clarification.

One test for ignition is to hook one lead of the test light to the ground side of the coil (terminal 1) and crank the engine. A flickering light, like a bouncing tach, usually indicates a working ignition system to the coil.

I usually test the center coil wire one of two ways. First is with a timing light. If I don't have the timing light handy, I put a spark plug in the distributor end of the wire, lay the plug on the manifold, and crank. (I used to hold the exposed end of the wire to the block, but went to the spark plug method after getting lit up one rainy night.)

Any idea how long since a timing belt change?

Good luck.

Something to check that won’t cost any $’s......
The internal connections inside the Rex coils have a way of causing trouble with age. I had that problem on our long-gone 740 Rex-Regina. It can be disassembled via the two torx screws that are positioned caddy cornered to each other. As I recall you might have to unbolt the whole assembly from its mounting. Once inside the coil/power stage you will find two or three contacts that come together when it’s fully assembled. Clean both the pins on the one half and the receiving “clips” on the other side. I remember tweaking the clips with needle nose pliers to create a more firm connection with the pins. Clean the oxidation off of all mating surfaces including where the assembly mounts to the car. The whole job takes about 15 minutes max.