Which trains from Tateyama to Tokyo

I will be purchasing a JR East Pass.
Which trains can I take from Tateyama to Tokyo/Shinjuku on the JR East Pass?

None. JR East pass no suitable.

Nagano would be closest station to access the Alpine route.

Shinano-Omachi Station on the opposite side of the Alpine Route is the closest station that is covered by the JR East Niigata Nagano Area Pass.

If you refer to the Tateyama in Chiba Prefecture, then any JR train to Tokyo will be covered:
http://www.hyperdia.com/

Upon further research I think the following will work:

Time Route

16:17 TATEYAMA(TOYAMA)
Station timetable | Add to favorite

[70 Min] • Toyama Chiho Railway Tateyama Line for DENTETSUTOYAMA
Train timetable | Interval timetable

17:27
17:27 DENTETSUTOYAMA
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[7 Min] • Walk
17:34
18:15 TOYAMA
[ Departure track No.11 ]
Station timetable | Add to favorite

[46 Min] • SHINKANSEN KAGAYAKI 514
Train timetable | Interval timetable

19:01
NAGANO
[ Arrival track No.13 ]
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Take time: 80 Minutes Transfer: 0 Times Distance: 222.4 km
Time Route

19:03 NAGANO
[ Departure track No.13 ]
Station timetable | Add to favorite

[80 Min] • SHINKANSEN KAGAYAKI 514
Train timetable | Interval timetable

20:23
TOKYO
[ Arrival track No.21 ]
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What do you think?

Half of that route is not covered by the JR East pass.

Which JR East Pass, for starters? There are two.

JR East Nagano Niigata Area Pass covers these trains:
Tokyo - Nagano
SHINKANSEN KAGAYAKI 503
or
LTD. EXP AZUSA 3
Toyama - Tokyo
SHINKANSEN KAGAYAKI 514
SHINKANSEN HAKUTAKA 578

JR EAST PASS (Nagano, Niigata area) only covers Hokuriku Shinkansen between Tokyo to Joetsumyoko only. It costs Y4,530 for unreserved seat for Toyama to Joetsumyoko sector.
https://www.jreast.co.jp/e/eastpass_n/
https://www.japan-guide.com/e/e2361_nagano_niigata.html