Short answer. No. Rule 18 states that the order of the court to submit the case for judgment under this Rule shall not be the subject of appeal or certiorari — so you cannot challenge that specific order right away through either remedy.
What the law says
The order of the court to submit the case for judgment pursuant to this Rule shall not be the subject to appeal or certiorari.
Rule 18, Section 10 — Judgment after pre. Read the full provision →
When the court can skip straight to judgment
Rule 18, Section 10 lets the court bypass a full trial in specific circumstances: should there be no more controverted facts, or no more genuine issue as to any material fact, or an absence of any issue, or should the answer fail to tender an issue, the court shall... motu proprio include in the pre-trial order that the case be submitted for summary judgment or judgment on the pleadings, without need of position papers or memoranda. The court can act on its own initiative once it sees the case genuinely presents no real factual dispute left to try, without either party needing to move for that outcome first.
The order itself cannot be appealed or challenged by certiorari
Rule 18 directly closes off the route you are asking about: the order of the court to submit the case for judgment pursuant to this Rule shall not be the subject to appeal or certiorari. That specific procedural order — the decision to submit the case for judgment rather than continue to a full trial — is not something you can challenge by an immediate appeal or a certiorari petition.
A ninety-day deadline follows the order
Once the case is submitted this way, the court is bound by a fixed timeline: in such cases, judgment shall be rendered within ninety calendar days from termination of the pre-trial. So while you cannot challenge the submission order itself, the rule does not leave the case open-ended — an actual judgment has to follow within that ninety-day window.
What this means for you
Because the bar in this rule applies specifically to the order submitting the case for judgment, not to the judgment itself, your objections about the case being decided this way are something to raise once that judgment on the merits is actually rendered, rather than through an immediate challenge to the submission order. Waiting for the judgment does not waive whatever arguments you have against the way the case was decided — it simply means those arguments have to be raised against the judgment, not against the earlier procedural order that led to it.