try to import the repository again, if you have a backup. don't play with the metadata, it is difficult to recover. Handle it using tools provided with B2B
It is very hard to recover the tp_MyCompany.xml .
And we do not suggest to make any changes directly in metadata.
What are the artifacts you have created ?
If there was no artifacts, then take from the fresh system and try to upload the same file in the /soa/b2b MDS folder.
Or take export host TP from any other fresh system and try to import.
If there are artifacts created then please provide details here.