I have some scattered input here in no real order.
Ignition- there is the harebrained relay system that makes you have to turn the key off before you can try to start again.
-I guess it's a start inhibit relay, could be part of the problem.
i know whenever I'd let my caddy sit, water would go down the backside of the fusebox, and fill all the relays, and I'd have to pull the lids off and dump em out before half my stuff would work. wiggle inspect, and clean.
Confirm with a test light or meter the fuel shutoff so has power in both start and run positions.
Run a wire from B+ to the solenoid if in doubt. Does it click lightly w/ power? it should. with this powered, the engine is 'on' even if the rest of the car is not, and it wont turn off with the key.
you have the old type pump gear with 2 small holes. while correctly timed, the pump can be 180 out internally. only test I know is retime with the pin in the other hole, but you are probably getting pretty adept at this exercise by now.
I see you have some clear line, what is the flow in and out like? direction? bubbles? did you prime the pump with some kind of fuel? If it's hard to see, you can pull the fuel filter off, and dump a bit of ATF in to make it nice and red.
I find after a long hiatus, or an out of fuel event, an otherwise fine diesel often has trouble getting enough cranking speed to purge air and prime everything, but a brisk 3rd gear(key on) drag behind a truck takes care of it without smoking 3 sets of batteries. Battery, jumper cable size, and jump car battery size all play a big role, the helo kitty cables you found in your girlfriends trunk won't cut it in the diesel world.
Glows- I don't see how you are activating or testing them. do they or the light work with the key? if so, good news for ignition switch, but not necessarily for the safety mechanism I mentioned earlier. If you activate them, battery voltage should drop noticeably if you have a decent way of measuring it. cycle them twice, and you can detect it with an IR pyrometer pointed at the connector if they work. Super rough test- undo the big glow fuse on the firewall (has been checked I hope), and hit the downstream(to GP) terminal with a jumper cable from battery +...if it doesn't spark a little, they are all dead.
I'm a bad person, some times in these cases, I use starter fluid NEver use starting fluid on a diesel. it's easy to get wrong, but not so hard to do right.
1 unplug the glow relay or fuse.
2 while cranking the engine, spray one puff tangental to the air inlet snorkel ,a few inches outboard(so a tiny whiff of fog gets sucked in). Continue to crank another 20 seconds. No-go, repeat, but shoot 2 puffs across the bow.
3 still no love, and want to take some risks(ranging from burned out glow plugs to broken rings and a dead engine) hook the glow plugs back up, run them 2 seconds, and go back to step 2. alternate; run the glows a full cycle, then just wait 40+ sec before you try to start the car, and you can try progressively shorter increments.
If it starts, you will likely have to give some throttle to keep it running till it purges and smooths out.
If it fires, and makes a painful knocking noise, you used waaay too much spray.
Despite the dire warnings, I've yet to fry a motor using the stuff, and we've been starting our 7.3 dump truck this way about 5 years.
Running ether and glows at the same time seems to kill the glow plugs pretty fast though.