getting the error message from another trigger in sql server
Based on the problem description, I tried to create a similar scenario including the solution. Hope this will help you.

Here I created tables and triggers.

Trigger trgEvents inserting the EventId into tbl_Position table if the EventId does not exists.

In the trigger trgPosition created on tbl_Position, I'm just validating whether column PositionId in tbl_Position is having a numeric value.

DROP TABLE IF EXISTS tbl_Events
GO
CREATE TABLE tbl_Events
(
EventId int PRIMARY KEY,
EventDescription varchar(512)
);
DROP TABLE IF EXISTS tbl_Position
GO
CREATE TABLE tbl_Position
(
EventId int REFERENCES tbl_Events(EventId),
PositionId varchar(8)
);
GO

DROP TRIGGER IF EXISTS trEvents
GO
CREATE TRIGGER trEvents
ON tbl_Events
FOR INSERT
AS
BEGIN
BEGIN TRY
IF EXISTS (select 'Exists ?' from tbl_Position P join inserted i on P.EventId=i.EventId)
    BEGIN
    UPDATE P SET PositionId=i.EventId+100 from tbl_Position P join inserted i on P.EventId=i.EventId;
    END
ELSE
    BEGIN
    INSERT INTO tbl_Position
    SELECt EventId,'NA' FROM inserted;
    END
END TRY
BEGIN CATCH
ROLLBACK;

DECLARE @Err NVARCHAR(4000) = ERROR_MESSAGE()
        RAISERROR(@Err, 16, 10);
END CATCH
END
GO

DROP TRIGGER IF EXISTS trPosition
GO
CREATE TRIGGER trPosition
ON tbl_Position
FOR UPDATE,INSERT
AS
BEGIN
IF (SELECT isnumeric(PositionId) from inserted)=1
    BEGIN
    Print 'PositionId has Numeric value'
    END
ELSE
    BEGIN
    RAISERROR ('PositionId has Non-Numeric value', 16 ,10)
    ROLLBACK;
    END
END


After I insert bellow execute the INSERT statement below.

INSERT INTO tbl_Events(EventId,EventDescription)
VALUES(1,'Dance compatition in New Delhi')


It fails and complete transaction gets rolled back.

(0 rows affected)
Msg 50000, Level 16, State 10, Procedure trEvents, Line 21 [Batch Start Line 62]
PositionId has Non-Numeric value
Msg 3609, Level 16, State 1, Line 63
The transaction ended in the trigger. The batch has been aborted.


Thanks!