en.wikipedia.org/wiki/MyGO!!!!!

Official sources identify 『迷跡波』 (Meisekiha) as MyGO!!!!!'s 1st album, and Oricon lists it with a highest rank of 5 in its album rankings. That means the page's wording is using the wrong chart type: this was an album-chart result, not a placement on an 'Oricon radio chart.'

• BanG Dream!'s official discography calls 『迷跡波』 a 1st Album released on 2023-11-01.
• Oricon's listing for the same title classifies it under albums and shows 最高順位 5位.

So the "5th" part is supported, but the claim is still factually incorrect because it misidentifies the chart as a radio chart.

This count is too low.

The band's own official discography already shows 13 original songs on the 1st album alone in November 2023. After that, additional original songs were released in 2024:

1. 1st Album『迷跡波』 (2023-11-01) contains 13 tracks.
2. 4th Single『砂寸奏／回層浮』 (2024-03-20) adds 3 more songs: 砂寸奏, 回層浮, 処救生.
3. 5th Single『端程山』 (2024-07-24) adds 3 more songs: 端程山, 輪符雨, 孤壊牢.
4. The digital release 『過惰幻』 came out on 2024-09-28.

That brings the total to at least 20 original songs by September 2024, which is already well above 13 before 27 December 2024. So the statement "As of 27 December 2024, MyGO!!!!! has 13 original songs" is contradicted by the band's official release history.

The official BanG Dream! discography page for MyGO!!!!! 2nd Album『跡暖空』 gives the release date as 2024年12月18日(水). That directly contradicts the table entry listing "28 December" for this album.

So the release date in the table is off by 10 days.