Pass custom attributes in OIDC request

I have added an OpenId Identity Provider to my Keycloak instance and everything is connected but they are requiring some additional parameters. In particular, they are looking for some time based parameters and a transaction UUID (jti). In the example below everything is good except for jti, exp, iat, and nbf.

How can I configure my Identity Provider in keyloak to provide these values in the request?

"sub": "",
"iss": "",
"nonce": "b67bc656-d15f-45f9-b1b9-90d704e9ae75",
"aud": "",

"grant_type": "password",
"acr_values": "",
"scope": " company.prRagioneSociale",
"redirect_uri": "http://localhost:8082/jmy/redirect-url",   
"prompt": "none|[login select_account consent]",

"nbf": 1501077865005,
"exp": 1501077895005,
"iat": 1501077865005,
"jti": "784da2d2-3333-4444-555-290583df81a7"