やむを得ない・止むを得ない

no choice but to ....　他に選択肢が無い

If determined that the items that were provided did not successfully meet the conditions then there will be no choice but to discard it.

（提供していただいたものが条件に適さないと判断された場合、止むを得ずこちらで破棄させていただくことがあります）

have to, be necessary/forced to   ～する必要がある

日常的）have to   中和的）be necessary to   強制的）be forced to

In the case that it is determined that the submitted items do not meet the prescribed conditions, we may be forced to dispose of the said items.

said items  当該品 

out of my control　コントロールできない

There were some circumstances that I had no way of changing and I ended up refusing.

（どうしても変更できない事情があってお断りすることにしました）

There were some circumstances that were out of my control.

（止むを得ない事情があって）

There were some circumstances that were out of my control, so I had to refuse the invitation.

（止むを得ない事情があって、招待を断らなければならなかった）

extenuating/unavoidable circumstances   止むを得ない事情

extenuating　/ɪk'stenjueɪtɪŋ/　adj)酌量すべき

unavoidable　/,ʌnə'vɔɪdəbl/　adj)避けられない