A disaster under the wood?

[englishman_ca]

The crack at the back is quite common to see. There are no doubt many great shooting rifles with a similar crack unknown to their owners. The tie plate is doing its job.

Epoxy might be a little difficult to get in there, plus the surface has to be oil free for epoxy glue to adhere. A syringe squirting acetone might clean it out, but keep it off the surface finish, which might be difficult.

If you must try to fix that crack, then use super glue and clamp it tight.
Super glue, or cyanoacrylate as it is known is not sensitive to oil. It is great stuff for certain applications. With a fine glue line, the crack will not open up there again. If it does crack, it will be in the wood beside the glue line.

Cyanoacrylate Set - Lee Valley Tools

Of course, the best fix would be a replacement fore stock. A lot depends on how many rounds you intend to put through it. Casual plinking with light loads, or heavy duty long strings at the range.
For now, if it shoots ok, I would probably just keep shooting the rifle and see what happens, making sure all screws are tight, and keeping an eye the wood directly in front of the trigger guard front screw. If the stock were to degenerate further, a crack would likely appear here.
Known as 'the damned crack', it was routinely repaired by gluing and fitting a cross screw. A Brit armourers' technique that was extensively used in India by Ishapore Arsenal. Hence the term 'Ishy screw'.